SEC Petition Evaluation Report

Petition SEC-00250 

Report Rev Number: 0

Report Submittal Date: 07/17/2019

Subject Expert(s): Paul Demopoulos, Joe Guido

Site Expert(s): N/A

Petition Administrative Summary

Petition Under Evaluation

Petition Number: SEC-00250

Petition Type: 83.13

Petition Receipt Date: November 1, 2018

Qualification Date: March 6, 2019

DOE/AWE Facility Name: Y-12

Petition Class

Petitioner-Requested Class 

Definition:

All workers who worked in any area of Y-12 where uranium was fabricated or 

processed from January 1, 1980, to December 31, 2000. 

Class Evaluated by NIOSH: All employees of the Department of Energy, its predecessor agencies, and their 

contractors and subcontractors who worked at the Y-12 Plant in Oak Ridge, 

Tennessee that may have incurred thorium exposures, during the period from 

January 1, 1977 through December 31, 1994 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. 

NIOSH-Proposed Class(es) to be 

Added to the SEC:

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

contractors and subcontractors who worked at the Y-12 Plant in Oak Ridge, 

Tennessee, during the period from January 1, 1977 through July 31, 1979 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 Number(s): SEC-00018

SEC-00028 

SEC-00098 

SEC-00186 

SEC-00251 

Petition Type: 83.13

83.13 

83.14 

83.14 

83.14

DOE/AWE Facility Name: Y-12 Plant

Y-12 Plant 

Y-12 Plant 

Y-12 Plant

Y-12 Plant
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SEC Petition Tracking Number(s): SEC-00018

SEC-00028 

SEC-00098 

SEC-00186 

SEC-00251

Petition Status: Class added to the SEC for March 1943 through December 31, 1947

Class added to the SEC for January 1948 through December 31, 1957 

Class added to the SEC for March 1, 1943 through December 31, 1947 

Class added to the SEC for January 1, 1948 through December 31, 1957 

Class added to the SEC for January 1, 1958 through December 31, 1976 

Related Evaluation Report Information 

Report Title: SEC Petition Evaluation Report for Petition SEC-00018

SEC Petition Evaluation Report for Petition SEC-00028 

SEC Petition Evaluation Report for Petition SEC-00098 

SEC Petition Evaluation Report for Petition SEC-00186 

SEC Petition Evaluation Report for Petition SEC-00251 

DOE/AWE Facility Name: Y-12 Plant

ORAU Preparation and Review

ORAU Lead Technical Evaluator: Paul Demopoulos

ORAU Peer Review Completed By: Patrick McCloskey

DCAS Review and Approval

Peer Review Completed By:

[Signature on File]

Lara Hughes 

July 17, 2019

SEC Petition Evaluation Reviewed By:

[Signature on File]

Timothy Taulbee 

July 17, 2019 

SEC Petition Evaluation Approved By:

[Signature on File]

Grady Calhoun 

July 17, 2019 
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Evaluation Report Summary: SEC-00250, Y-12 Plant

The National Institute for Occupational Safety and Health (NIOSH) prepared this evaluation report in 

response to a petition to add a class of workers at the Y-12 Plant to the Special Exposure Cohort 

(SEC). The Energy Employees Occupational Illness Compensation Program Act of 2000, as 

amended, (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, describe the process for adding new classes to the SEC.

Petitioner-Requested Class Definition

NIOSH received petition SEC-00250 on November 1, 2018 and qualified it on March 6, 2019. The 

petitioner requested that NIOSH consider the following class: All workers who worked in any area of 

Y-12 where uranium was fabricated or processed from January 1, 1980, to December 31, 2000.

Class Evaluated by NIOSH

Based on its preliminary research, NIOSH modified the petitioner-requested class. NIOSH evaluated 

the following class: All employees of the Department of Energy, its predecessor agencies, and their 

contractors and subcontractors who worked at the Y-12 Plant in Oak Ridge, Tennessee that may have 

incurred thorium exposures, during the period from January 1, 1977 through December 31, 1994 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.

NIOSH Determination about the Proposed Class(es) to be Added to the SEC

NIOSH has defined a single class of employees for which NIOSH cannot estimate radiation doses 

with sufficient accuracy. The NIOSH-proposed class includes: All employees of the Department of

Energy, its predecessor agencies, and their contractors and subcontractors who worked at the Y-12 

Plant in Oak Ridge, Tennessee, during the period from January 1, 1977 through July 31, 1979 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.

Feasibility of Dose Reconstruction

Following its analysis of the SEC-00250 Y-12 class under evaluation (January 1, 1977 through 

December 31, 1994), NIOSH’s conclusions fell into three time periods, as follows:

1. 1977-1979: NIOSH finds it is not feasible to estimate internal exposures with sufficient accuracy 

for all employees at the site from January 1, 1977 through July 31, 1979 due to a lack of sufficient 

thorium-related lung count data for this period.

2. 1979-1986: For the period from August 1, 1979 through December 31, 1986, per EEOICPA and 

42 C.F.R. § 83.13(c) (1), NIOSH has established that it has access to sufficient information to: (1) 

estimate the maximum radiation dose, for every type of cancer for which radiation doses are 

reconstructed, that could have been incurred in plausible circumstances by any member of the 

class; or (2) estimate radiation doses of members of the class more precisely than an estimate of 
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the maximum dose. The information available from the site profile and additional resources is 

sufficient to estimate the maximum internal and external potential exposure to members of the 

evaluated class under plausible circumstances during the specified period from August 1, 1979 

through December 31, 1986. 

3. 1987-1994: NIOSH is currently working with the Y-12 site to receive post-1986 thorium data that 

may allow NIOSH to estimate the maximum internal potential exposure from thorium during the 

period from January 1, 1987 through December 31, 1994 (discussed below). Until these thorium 

progeny data become available, NIOSH is reserving its evaluation of internal exposure from 

thorium for the period from January 1, 1987 through December 31, 1994.

With the exception of the reserved internal thorium feasibility determination for 1987-1994, per 

EEOICPA and 42 C.F.R. § 83.13(c)(1), NIOSH has established that it has access to sufficient 

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

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

member of the class; or (2) estimate radiation doses more precisely than an estimate of maximum 

dose. There is enough information available from the site profile and additional resources to 

document or estimate the maximum external and maximum non-thorium internal potential 

exposures to members of the evaluated class under plausible circumstances during the specified 

period from January 1, 1987 through December 31, 1994. 

The current NIOSH dose reconstruction feasibility findings are based on the following: 

• Principal sources of internal radiation for members of the evaluated class include inhalation and 

ingestion of uranium, thorium (and progeny), and calutron-cyclotron-related radioisotopes from 

processing and production operations. 

• In NIOSH’s 2018 evaluation of the Y-12 Plant, SEC Petition Evaluation Report for Petition 

SEC-00251, Y-12 Plant (NIOSH, 2018), NIOSH found that available in-vivo monitoring data for 

thorium (i.e., lung counts) during the period from January 1, 1959 through December 31, 1976 

were recorded in total thorium mass units. As such, NIOSH lacked the ability to use these data to 

determine the associated quantities of thorium-232, thorium-228, and radium-228 with sufficient 

accuracy. Consequently, a class of Y-12 Plant workers was added to the SEC for the period from 

January 1, 1958, through December 31, 1976. 

• Consistent with the findings of NIOSH’s 2018 evaluation, NIOSH has now determined that there 

are also insufficient in-vivo monitoring data for thorium (i.e., lung counts) during the period from 

January 1, 1977 through July 31, 1979. Available thorium lung count data during this period are 

also mass-based results. As such, NIOSH does not have the ability to use these data to determine 

the associated intakes of thorium-232, thorium-228, and radium-228 with sufficient accuracy. 

Thus, NIOSH cannot determine with sufficient accuracy the internal exposures from thorium lung 

measurements during the period from January 1, 1977 through July 31, 1979. 
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• For the period from August 1, 1979 through December 31, 1986, NIOSH has determined that 

there are sufficient activity-based Pb-212 and Ac-282 in-vivo monitoring data to allow NIOSH to 

determine the associated intakes of Th-232, Th-228, and Ra-228 with sufficient accuracy. 

• NIOSH is currently working with the Y-12 site to receive post-1986 activity-based thorium 

progeny data (i.e., Ac-228 and Pb-212) that may allow NIOSH to estimate the maximum internal 

potential exposure from thorium to members of the evaluated class during the period from January

1, 1987 through December 31, 1994. Therefore, NIOSH is reserving its evaluation of internal 

exposure from thorium for the period from January 1, 1987 through December 31, 1994 until 

activity-based thorium progeny data are available.

• NIOSH has determined that there are sufficient in-vivo and in-vitro monitoring data for uranium 

(i.e., lung counts and urinalysis) during the period from January 1, 1977 through December 31, 

1994 to allow NIOSH to determine the potential intakes of uranium with sufficient accuracy.

• NIOSH has determined that there are currently sufficient calutron-cyclotron-related radioisotope 

data to estimate the maximum internal potential exposure to members of the evaluated class during 

the period from January 1, 1977 through December 31, 1994 for Isotopes Group workers on the 

Y-12 campus based on the evaluation contained in ORAUT-RPRT-0090.

• Principal sources of external radiation for members of the evaluated class included exposures to 

beta particles, gamma photons, and neutrons. The radiation sources potentially contributing to 

these exposures would have principally included processing operations related to uranium, 

thorium (and progeny), and calutron-cyclotron-related radioisotopes.

• Beta, photon, and neutron monitoring data are available for Y-12 in the form of individual 

dosimetry during the evaluation period from January 1, 1977 through December 31, 1994. 

Consistent with its findings in prior NIOSH evaluations of the Y-12 Plant, NIOSH finds that there 

is sufficient monitoring and source term information available to reconstruct external and medical 

X-ray doses for all workers at the Y-12 Plant during the period from January 1, 1977 through 

December 31, 1994. 

• Pursuant to 42 C.F.R. § 83.13(c)(1), for the period from January 1, 1977 through July 31, 1979, 

NIOSH has 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 during the period from January 1, 1977 through July 31, 1979, 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

Per EEOICPA and 42 C.F.R. § 83.13(c)(3), a health endangerment determination is required because 

NIOSH has determined that it does not have sufficient information to estimate dose for the members 

of the proposed class from January 1, 1977 through July 31, 1979.

For the period from January 1, 1987, through December 31, 1994, a health endangerment 

determination will be provided, as required, when a dose estimation feasibility evaluation has been 

completed (following the expected receipt of additional Y-12 thorium data).

NIOSH did not identify any evidence supplied by the petitioners or from other resources that would 

establish that the proposed class was exposed to radiation during a discrete incident likely to have 

involved exceptionally high-level exposures. However, evidence indicates that some workers in the 

proposed class have accumulated possible chronic exposures through intakes of radionuclides, 

combined with external exposures to gamma, beta, and neutron radiation. In the absence of high-level 

incident exposures, 42 C.F.R. § 83.13(c)(3)(ii) requires NIOSH to specify that health was endangered 

for those workers covered by this evaluation who were employed for at least 250 aggregated work 

days either solely under this employment or in combination with work days within the parameters 

established for one or more other SEC classes.
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Table of Contents

Evaluation Report Summary: SEC-00250, Y-12 Plant ........................................................................... 3

Table of Contents .................................................................................................................................... 7

1.0 Purpose and Scope ........................................................................................................................ 11

2.0 Introduction .................................................................................................................................. 11

3.0 SEC-00250, Y-12 Plant Class Definitions ................................................................................... 13

3.1 Petitioner-Requested Class Definition and Basis ................................................................ 13

3.2 Class Evaluated by NIOSH ................................................................................................. 14

3.3 NIOSH Determination about the Proposed Class(es) to be Added to the SEC ................... 14

4.0 Data Sources Reviewed by NIOSH to Evaluate the Class ........................................................... 14

4.1 Site Profile Technical Basis Documents (TBDs) ................................................................ 15

4.2 ORAU Technical Information Bulletins (OTIBs) ............................................................... 15

4.3 Facility Employees and Experts .......................................................................................... 16

4.4 Previous Dose Reconstructions ........................................................................................... 17

4.5 NIOSH Site Research Database .......................................................................................... 18

4.6 Delta View Imaging System ................................................................................................ 18

4.7 Y-12 Electronic Records System ......................................................................................... 18

4.8 ORAU Center for Epidemiologic Research Database ......................................................... 18

4.9 Documentation Provided by Petitioners .............................................................................. 19

5.0 Radiological Operations Relevant to the Class Evaluated by NIOSH ......................................... 20

5.1 Y-12 Plant and Process Description .................................................................................... 21

5.1.1 Y-12 Key Uranium Processes ................................................................................. 21

5.1.2 Y-12 Thorium Processes ......................................................................................... 23

5.1.3 Isotopes Group Activities ........................................................................................ 25

5.1.4 Weapons Assembly and Disassembly ..................................................................... 26

5.2 Radiological Exposure Sources from the Y-12 Plant Operations ....................................... 27

5.2.1 Internal Radiological Exposure Sources from the Y-12 Plant Operations .............. 27

5.2.1.1 Uranium .................................................................................................... 27

5.2.1.2 Thorium .................................................................................................... 27

5.2.1.3 Radionuclides Produced and/or Handled by the Isotopes Group ............. 28

5.2.2 External Radiological Exposure Sources from the Y-12 Plant Operations ............. 29

5.2.2.1 Photon ....................................................................................................... 29

5.2.2.2 Beta ........................................................................................................... 30

5.2.2.3 Neutron ..................................................................................................... 30

6.0 Summary of Available Monitoring Data for the Class Evaluated by NIOSH ............................. 31

6.1 Available Y-12 Plant Internal Monitoring Data .................................................................. 32

6.1.1 Available Uranium Data .......................................................................................... 32

6.1.2 Available Thorium Data .......................................................................................... 34

6.2 Available Y-12 Plant External Monitoring Data ................................................................. 36
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7.0 Feasibility of Dose Reconstruction for the Class Evaluated by NIOSH ...................................... 37

7.1 Pedigree of Y-12 Plant Data ................................................................................................ 37

7.1.1 Internal Monitoring Data Pedigree Review ............................................................. 38

7.1.2 External Monitoring Data Pedigree Review ............................................................ 39

7.2 Evaluation of Bounding Internal Radiation Doses at Y-12 Plant ........................................ 39

7.2.1 Evaluation of Bounding Process-Related Internal Doses ........................................ 39

7.2.1.1 Urinalysis Information and Available Data .............................................. 40

7.2.1.2 Lung Counting Information and Available Data ...................................... 40

7.2.1.3 Airborne Levels ........................................................................................ 41

7.2.2 Evaluation of Bounding Ambient Environmental Internal Doses ........................... 41

7.2.3 Methods for Bounding Internal Dose at the Y-12 Plant .......................................... 41

7.2.3.1 Methods for Analyzing Uranium Bioassay Data ...................................... 42

7.2.3.2 Methods for Analyzing Thorium Bioassay Data ...................................... 42

7.2.4 Internal Dose Reconstruction Feasibility Conclusion ............................................. 43

7.3 Evaluation of Bounding External Radiation Doses at Y-12 Plant ...................................... 43

7.3.1 Evaluation of Bounding Process-Related External Doses ....................................... 44

7.3.2 Evaluation of Bounding Ambient Environmental External Doses .......................... 45

7.3.3 Y-12 Plant Occupational X-Ray Examinations ....................................................... 45

7.3.4 Methods for Bounding External Dose at Y-12 Plant ............................................... 45

7.3.4.1 Methods for Bounding Operational Period External Dose ....................... 45

7.3.4.2 Methods for Bounding Ambient Environmental External Doses ............. 46

7.3.5 External Dose Reconstruction Feasibility Conclusion ............................................ 46

7.4 Evaluation of Petition Basis for SEC-00250 ....................................................................... 47

7.4.1 Uranium and Thorium Contamination Existed in the Machine Shop ..................... 47

7.4.2 Petition Basis E.5. - Four Statements of Concern ................................................... 47

7.4.3 Petition Basis F.1. - One Statement of Concern ...................................................... 48

7.4.4 Petition Basis F.2. - One Statement of Concern ...................................................... 49

7.4.5 Petition Basis F.4. - One Document and Several Statements of Concern ............... 49

7.5 Summary of Feasibility Findings for Petition SEC-00250 .................................................. 51

8.0 Evaluation of Health Endangerment for Petition SEC-00250 ...................................................... 52

9.0 Class Conclusion for Petition SEC-00250 ................................................................................... 52

10.0 References .................................................................................................................................... 55

Attachment One: Data Capture Synopsis .............................................................................................. 61
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Tables 

Table 4-1: No. of Y-12 Plant Claims Submitted Under the Dose Reconstruction Rule ....................... 17

Table 5-1: Key Uranium Operations ..................................................................................................... 21

Table 5-2: Y-12 Buildings Involved in Initial Thorium Operations ..................................................... 23

Table 6-1: Summary of Available CER Data ........................................................................................ 33

Table 6-2: Type Analysis Chart ............................................................................................................ 33

Table 6-3: Uranium-related Records 1977-1986 ................................................................................... 34

Table 6-4: Summary of Available CER (External Dose) Data ............................................................. 36

Table 7-1: Thorium Records 1979-1986 ............................................................................................... 40

Table 7-2: Summary of Feasibility Findings for SEC-00250 ............................................................... 51

Table A1-1: Summary of Holdings in the SRDB for the Y-12 Plant .................................................... 61

Table A1-2: Database Searches for the Y-12 Plant ............................................................................... 80

Figures 

Figure 5-1: Thorium Flow Chart for Contamination Control ............................................................... 24

Figure 5-2: Activities in a Purified Thorium Sample ............................................................................ 28

Figure 6-1: Thorium Lung Count Measurements .................................................................................. 35
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SEC Petition Evaluation Report for SEC-00250

ATTRIBUTION AND ANNOTATION: This is a single-author document. Unless otherwise noted for 

specific sections in this report, all conclusions drawn from the data presented in this evaluation were 

made by the ORAU Team Lead Technical Evaluator: Paul Demopoulos, 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 radiation doses for all employees of the 

Department of Energy, its predecessor agencies, and their contractors and subcontractors who worked 

at the Y-12 Plant in Oak Ridge, Tennessee that may have incurred thorium exposures, during the 

period from January 1, 1977 through December 31, 1994 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. It provides information and analyses 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. This report also does not contain the final determination as to whether the proposed class 

will be added to the SEC (see Section 2.0).

This evaluation was conducted in accordance with the requirements of EEOICPA, 42 C.F.R. pt. 83, 

and the guidance contained in the Division of Compensation Analysis and Support’s (DCAS) Internal 

Procedures for the Evaluation of Special Exposure Cohort Petitions, DCAS-PR-004.1

1 DCAS was formerly known as the Office of Compensation Analysis and Support (OCAS).

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

the detailed implementation guidelines available on the NIOSH Radiation Dose Reconstruction Program webpage. 

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 (DHHS) 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 class of employees through NIOSH dose 

reconstructions.2

 
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42 C.F.R. § 83.13(c)(1) states: Radiation doses can be estimated with sufficient accuracy if NIOSH 

has established that it has access to sufficient information to estimate the maximum radiation dose, 

for every type of cancer for which radiation doses are reconstructed, that could have been incurred in 

plausible circumstances by any member of the class, or if NIOSH has established that it has access to 

sufficient information to estimate the radiation doses of members of the class more precisely than an 

estimate of the maximum radiation dose.

Under 42 C.F.R. § 83.13(c)(3), if it is not feasible to estimate with sufficient accuracy radiation doses

for members of the class, then NIOSH must determine that there is a reasonable likelihood that such 

radiation doses may have endangered the health of members of the class. The regulation requires 

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 

employees who were employed for at least 250 aggregated work days within the parameters 

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

or more other SEC classes. 

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 petitioner(s) and the 

Advisory Board on Radiation and Worker Health (Advisory Board). The Advisory Board will 

consider the NIOSH evaluation report, together with the petition, petitioner(s) comments, and other 

information the Advisory Board considers appropriate, in order to make recommendations to the 

Secretary of DHHS 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 Advisory Board, the Director of NIOSH will 

propose a decision on behalf of DHHS. The Secretary of DHHS will make the final decision, taking 

into account the NIOSH evaluation, the advice of the Advisory Board, and the proposed decision 

issued by NIOSH. As part of this decision process, petitioners may seek a review of certain types of 

final decisions issued by the Secretary of DHHS.

3

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

available on the 

 

NIOSH Radiation Dose Reconstruction Program webpage.
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3.0 SEC-00250, Y-12 Plant Class Definitions 

The following subsections address the evolution of the class definition for SEC-00250, Y-12 Plant. 

When a petition is submitted, the requested-class definition is reviewed as submitted. Based on its 

review of the available site information and data, NIOSH will make a determination whether to 

qualify for full evaluation all, some, or no part of the petitioner-requested class. If some portion of the 

petitioner-requested class is qualified, NIOSH will specify that class along with a justification for any 

modification of the petitioner’s class. After a full evaluation of the qualified class, NIOSH will 

determine whether to propose a class for addition to the SEC and will specify that proposed class 

definition. 

NOTE: NIOSH is currently working with the Y-12 site to receive post-1986 activity-based thorium 

progeny data (i.e., Ac-228 and Pb-212) that may allow NIOSH to estimate the maximum 

internal potential exposure from thorium to members of the evaluated class during the period 

from January 1, 1987 through December 31, 1994. Therefore, NIOSH is reserving its 

evaluation of internal exposure from thorium for the period from January 1, 1987 through 

December 31, 1994 until activity-based thorium progeny data are available.

3.1 Petitioner-Requested Class Definition and Basis

NIOSH received petition SEC-00250 on November 1, 2018, and it qualified on March 6, 2019. The 

petitioner requested that NIOSH consider the following class: All workers who worked in any area of 

Y-12 where uranium was fabricated or processed from January 1, 1980, to December 31, 2000.

The petitioner submitted documentation asserting that reconstruction of internal dose at Y-12 was not 

feasible. NIOSH assessed these documents and discussed the issues voiced by the petitioner in a 

consultation call. The petitioner provided additional information to support the petitioner’s belief that 

accurate dose reconstruction is not feasible for Y-12 employees due to a NIOSH self-identified need 

for additional research into the feasibility of reconstructing internal doses to thorium after 1976, as 

presented in a previous SEC evaluation report for Y-12 (SEC-00251) (NIOSH 2018). Even though 

NIOSH has access to Y-12 in-vivo monitoring from January 1, 1977 through December 31, 1994, it 

still needed to evaluate whether sufficient activity-based lung count data are available to establish a 

sufficiently accurate assessment of the thorium dose. After consideration, NIOSH deemed the 

following information sufficient to qualify SEC-00250 for evaluation: 

NIOSH currently finds support to qualify petition SEC-00250 for evaluation for thorium 

exposures from January 1, 1977 to December 31, 1994, based upon a NIOSH 

self-identified infeasibility when using in-vivo lung counting data for thorium exposures. 

In NIOSH’s previous evaluation of SEC-00251, it proposed an SEC class due to inability to 

bound potential thorium exposures for all employees of the Department of Energy, its 

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

Plant in Oak Ridge, Tennessee, during the period January 1, 1958 through December 31, 

1976 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. 
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The information and statements provided by the petitioner qualified the petition for further 

consideration by NIOSH, the Advisory Board, and DHHS. The details of the petition bases are 

addressed in Section 7.4.

3.2 Class Evaluated by NIOSH

NIOSH changed the start date of the petitioner-requested class from January 1, 1980 to January 1, 

1977 so the class would begin at the end of the prior Y-12 evaluation into the feasibility of 

reconstructing thorium dose, as indicated in the SEC-00251 evaluation report (NIOSH, 2018). 

NIOSH changed the end date of the petitioner-requested class from December 31, 2000 to December 

31, 1994. Beginning in September 1994, the plant was placed in a stand-down mode. This effectively 

stopped all routine work (and chronic exposure potential) in the process areas. Consequently, NIOSH 

used this event to establish the end date of the class qualifying for evaluation. Therefore, NIOSH 

defined the following class for further evaluation: All employees of the Department of Energy, its 

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

Ridge, Tennessee that may have incurred thorium exposures, during the period January 1, 1977 

through December 31, 1994 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.

3.3 NIOSH Determination about the Proposed Class(es) to be Added to the SEC

NIOSH has defined a single class of employees for which NIOSH cannot estimate radiation doses 

with sufficient accuracy. The NIOSH-proposed class to be added to the SEC includes: All employees 

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

worked at the Y-12 Plant in Oak Ridge, Tennessee, during the period January 1, 1977 through July 

31, 1979 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.

4.0 Data Sources Reviewed by NIOSH to Evaluate the Class

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

regarding the Y-12 Plant. The database search included the Department of Energy (DOE) Legacy 

Management Considered Sites database, the DOE Office of Scientific and Technical Information 

(OSTI) SciTech Connect database, and the Hanford Declassified Document Retrieval System. In 

addition to general Internet searches, the NIOSH Internet search included OSTI OpenNet searches, the

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

(ADAMS) web searches, and the DOE-National Nuclear Security Administration-Nevada Site Officesearch. Attachment One includes a summary of the Y-12 Plant documents. The summary specifically 

includes 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.
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4.1 Site Profile Technical Basis Documents (TBDs) 

A Site Profile provides specific information concerning the documentation of historical practices 

documented at the specified site. Dose reconstructors can use the Site Profile to evaluate internal and 

external dosimetry data for monitored and unmonitored employees, and to supplement or substitute 

for individual monitoring data. The Y-12 Site Profile consists of an Introduction and five Technical 

Basis Documents (TBDs) that provide process history information, information on personal and area 

monitoring, radiation source descriptions, and references to primary documents relevant to the 

radiological operations at the site. As part of NIOSH’s evaluation detailed herein, it examined the 

following TBDs for insights into Y-12 Plant operations or related topics/operations at other sites: 

• TBD for Y-12 National Security Complex Introduction, ORAUT-TKBS-0014-1; Rev. 01; October 

24, 2006; SRDB Ref ID: 30036 

• TBD for Y-12 National Security Complex – Site Description, ORAUT-TKBS-0014-2; Rev. 02; 

November 8, 2007; SRDB Ref ID: 36045 

• TBD for Y-12 National Security Complex – Occupational Medical Dose, ORAUT-TKBS-0014-3; 

Rev. 01; June 18, 2007; SRDB Ref ID: 32461 

• TBD for Y-12 National Security Complex – Occupational Environmental Dose, Rev. 01; ORAUTTKBS-0014-4; July 20, 2006; SRDB Ref ID: 30042 

• TBD for Y-12 National Security Complex – Occupational Internal Dose, Rev. 03; ORAUT-TKBS0014-5; March 12, 2012; SRDB Ref ID: 109202 

• TBD for Y-12 National Security Complex – Occupational External Dosimetry, Rev. 02; ORAUTTKBS-0014-6; December 18, 2009; SRDB Ref ID: 77701 

4.2 ORAU Technical Information Bulletins (OTIBs) 

An ORAU Technical Information Bulletin (OTIB) is a general working document that provides 

guidance for preparing dose reconstructions at particular sites or categories of sites. An ORAU 

Procedure provides specific requirements and guidance regarding EEOICPA project-level activities, 

including preparation of dose reconstructions at particular sites or categories of sites. NIOSH 

reviewed the following OTIBs as part of its evaluation:

• OTIB: Dose Reconstruction from Occupationally Related Diagnostic X-Ray Procedures, ORAUTOTIB-0006, Rev. 04; Oak Ridge Associated Universities; effective June 20, 2011; SRDB Ref ID: 

98147

• OTIB: Historical Evaluation of the Film Badge Dosimetry Program at the Y-12 Facility in Oak 

Ridge, Tennessee: Part 1 – Gamma Radiation, ORAUT-OTIB-0044, Rev. 01; Oak Ridge 

Associated Universities; effective April 29, 2013; SRDB Ref ID: 124944

• OTIB: Historical Evaluation of the Film Badge Dosimetry Program at the Y-12 Plant in Oak 

Ridge, Tennessee: Part 2 – Neutron Radiation, ORAUT-OTIB-0045, Rev. 01; Oak Ridge 

Associated Universities; effective November 30, 2009; SRDB Ref ID: 77243
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• OTIB: Historical Evaluation in the Film Badge Dosimetry Program at the Y-12 Plant in Oak 

Ridge, Tennessee: Part 3 – Beta Radiation, ORAUT-OTIB-0046, Rev. 00; Oak Ridge Associated 

Universities; effective June 22, 2007; SRDB Ref ID: 32523

• OTIB: Effect of Threshold Energy & Angular Response of NTA Film on Missed Neutron Dose at 

Oak Ridge Y-12, ORAUT-OTIB-0051, Rev. 00; Oak Ridge Associated Universities; effective 

May 15, 2006; SRDB Ref ID: 29977

• OTIB: Coworker External Dosimetry Data for the Y-12 National Security Complex, ORAUTOTIB-0064, Rev. 02, Oak Ridge Associated Universities; April 29, 2013; SRDB Ref ID: 124947

• OTIB: Potential Missed Dose to Nuclear Weapons Assemblers at the Y-12 Plant During the 

Period from 1958 to 1990, ORAUT-OTIB-0074, Rev. 00; Oak Ridge Associated Universities; 

effective March 13, 2009; SRDB Ref ID: 62716

• OTIB: Use of Claimant Datasets for Coworker Modeling, ORAUT-OTIB-0075, Rev. 01; Oak 

Ridge Associated Universities; effective June 17, 2016; SRDB Ref ID: 157060

• OTIB: Guiding Reconstruction of Intakes of Thorium Resulting from Nuclear Weapons Programs, 

ORAUT-OTIB-0076, Rev. 00, Oak Ridge Associated Universities; July 10, 2014; SRDB Ref ID: 

133669

• OTIB: Guidance on Assigning Occupational X-Ray Dose Under EEOICPA for X-Rays 

Administered Off Site, ORAUT-OTIB-0079, Rev. 01; Oak Ridge Associated Universities; 

effective March 18, 2016; SRDB Ref ID: 152173

4.3 Facility Employees and Experts

To obtain more information in support of its 2018 evaluation of petition SEC-00251, NIOSH 

interviewed six former Y-12 Plant employees. These six interviews were reviewed for this 

SEC-00250 effort; three of the interviews listed below (Personal Communications 2012, 2018d, and 

2018e) were determined to have information pertinent to the class currently under evaluation. In 

addition to these formal interviews, NIOSH has requested information from the Y-12 Knowledge 

Preservation Group; however, no additional information was provided. 

• Personal Communication, 2012, Personal Communication with Former Oak Ridge National 

Laboratory employee; Telephone Interview by ORAU Team and NIOSH; March 15, 2012, SRDB 

Ref. ID 110639

• Personal Communication, 2018a, Personal Communication with Former Y-12 Plant employee; 

In-person Interview by ORAU Team; August 15, 2018; SRDB Ref ID: 173936

• Personal Communication, 2018b, Personal Communication with Former Y-12 Plant employee; 

In-person Interview by ORAU Team; August 16, 2018; SRDB Ref ID: 173937

• Personal Communication, 2018c, Personal Communication with Former Y-12 Plant employee; 

In-person Interview by ORAU Team; August 16, 2018; SRDB Ref ID: 173938
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• Personal Communication, 2018d, Personal Communication with Former Y-12 Plant employee; 

In-person Interview by ORAU Team; August 16, 2018; SRDB Ref ID: 173939

• Personal Communication, 2018e, Personal Communication with Former Y-12 Plant employee; 

In-person Interview by ORAU Team; August 16, 2018; SRDB Ref ID: 174343

4.4 Previous Dose Reconstructions

NIOSH reviewed its NIOSH DCAS Claims Tracking System (referred to as NOCTS) to locate

EEOICPA-related dose reconstructions that might provide information relevant to the petition 

evaluation. Table 4-1 summarizes the results of this review. (NOCTS data available as of May 16, 

2019) 

Table 4-1: No. of Y-12 Plant Claims Submitted Under the Dose Reconstruction Rule

Description Totals

Total number of claims submitted for dose reconstruction 6525

Total number of claims submitted for energy employees who worked during the period under evaluation 

(January 1, 1977 through December 31, 1994). 3615

Total number of claims submitted for energy employees who started their employment during the period 

under evaluation (January 1, 1977 through December 31, 1994) 1825

Number of dose reconstructions completed for energy employees who worked during the period under 

evaluation (i.e., the number of such claims completed by NIOSH and submitted to the Department of Labor 

for final approval).

3211

Number of claims for which internal dosimetry records were obtained for the identified years in the 

evaluated class definition 1688

Number of claims for which external dosimetry records were obtained for the identified years in the 

evaluated class definition 3267

There are 3615 Y-12 claims with some employment between the years of 1977 and 1994. NIOSH 

reviewed each claim to determine whether internal and/or external personal monitoring records could 

be obtained for the employee. As indicated in Table 4-1, for employees who worked during the class 

period under evaluation, NIOSH has been able to obtain internal and external monitoring data for 

approximately 47% and 90% of the claims, respectively. The dose reconstruction claimant interviews 

(CATI) conducted with the claimants provide some detailed information regarding work locations, 

hours worked, incidents, and hazards encountered. The interviews also identified conditions for 

which there would have been potential for either internal or external exposures.
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4.5 NIOSH Site Research Database

NIOSH also examined its Site Research Database (SRDB) to locate documents supporting the 

assessment of the evaluated class. As of June 4, 2019, the SRDB contained 15,254 documents (5067 

main documents and 10,187 related subdocuments) that were identified as pertaining to the Y-12 

Plant. These documents were evaluated for their relevance to this petition. The documents include 

historical background on Y-12 plant processes, lung counting, urinalysis, fecal sampling, radiological 

control program, medical monitoring, and process materials. 

4.6 Delta View Imaging System

Maintained by Y-12, the Delta View Imaging System is comprised of scanned images of hard copy 

reports and monitoring data printouts associated with Y-12 personnel. Delta View stores copied 

images of documents and is searchable if keywords have been associated with the individual images 

when initially loaded. The images in Delta View are accessible by individual name and/or ID 

numbers, analysis, and sample type, among other parameters. Examples of data in Delta View 

include in-vivo lung counts, input forms, multi-channel analyzer output, gamma spectrometry 

images, and data from Y-12 and X-10 analytical labs. There were approximately 24,000 images of 

in-vivo-related documents obtained for the period from 1989 through 1995 (Delta View Data, 1989–

1995). 

4.7 Y-12 Electronic Records System

Maintained by the Y-12 internal dosimetry department, these data contain analytical results by 

individual, ID, bioassay type, date, and radionuclide. Y-12 provided to NIOSH an excerpt from this 

system in spreadsheet format containing 62,935 individual lung count records from 1984 through 

1995 (Lung Count Spreadsheet, 1984–1995). 

4.8 ORAU Center for Epidemiologic Research Database

From 1978 through the 1980s, the Y-12 Site delivered electronic files of worker data to the ORAU 

Center for Epidemiologic Research as a resource for the Health and Mortality Studies conducted for 

the DOE and its predecessor agencies. Included were records for Y-12 workers. This data are 

currently maintained by Oak Ridge Institute for Science and Education (ORISE) (Watkins, 1993).

NIOSH obtained the following datasets: 

• External Dosimetry dataset: 520,354 records covering the period 1950-1988 

• Internal in-vitro dataset: 479,446 records covering the period 1950-1988 

• The Internal in-vivo dataset: 66,274 records covering the period 1961-1988 
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4.9 Documentation Provided by Petitioners

In qualifying and evaluating the petition, NIOSH reviewed the following documents submitted by the 

petitioners:

• Cover letter for SEC-00250 from [name redacted], October 18, 2018; SRDB Ref ID: 176782, PDF 

pp. 20-21 

• Y-12 National Security Complex – Occupational Internal Dose, ORAUT-TKBS-0014-5, Rev. 03, 

Oak Ridge Associated Universities, March 12, 2012; SRDB Ref ID: 109202 

• Y-12 Uranium Exposure Study, Eckerman, K. F., and G. D. Kerr, ORNL/TM-1999/114, Lockheed 

Martin Energy Systems, Oak Ridge National Laboratory, Oak Ridge, Tennessee; August 5, 1999; 

SRDB Ref ID: 11600 

• Y-12 Plant Dosimetry Summary Report for [name redacted] SEC Petition, 2018, Special Exposure 

Cohort (SEC) Petition for Y-12 Plant (SEC-00250), National Institute for Occupational Safety and 

Health (NIOSH), November 1, 2018; SRDB Ref ID: 176782, PDF p. 22

• Y-12 Electrician Radiation Dose Report, no date, no author; SRDB Ref ID: 176789 

• Y-12 Radiation Dose Report 2; no date, no author; SRDB Ref ID: 176790 

• Memorandum to Defense Nuclear Facilities Safety Board for Oak Ridge Program, McConnell, 

J.J.; April 9, 1993; SRDB Ref ID: 57709

• DFNSB audit report Review of Chemical Safety at the Y-12 Plant, Van Holle, December 11, 1998; 

SRDB Ref ID: 176787, PDF pp. 7-8 

• NIOSH Dose Reconstruction Report for NOCTS Claim #[redacted], no author, no date; SRDB Ref 

ID: 176788

• Additional Supporting Document from Petitioner re Contaminated Machines, no date, no author;

SRDB Ref ID: 176786

• Letter to Defense Nuclear Facilities Safety Board from, G. Podonsky, (DOE), January 1996: 

SRDB Ref ID: 176785 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1980, no author, 

February 1982: SRDB Ref ID: 26888 

• Radiation Exposures Report for DOE and DOE Contractor Employees –1983, no author, March 

1983: SRDB Ref ID: 26890 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1982, no author, 

February 1984: SRDB Ref ID: 26892 
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• Radiation Exposures Report for DOE and DOE Contractor Employees – 1983, no author, 

October 1984: SRDB Ref ID: 26895 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1984, no author, 

December 1985: SRDB Ref ID: 26896 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1985, no author, 

December 1986: SRDB Ref ID: 26897 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1986, no author, 

December 1987: SRDB Ref ID: 26898 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1987, no author, 

October 1989: SRDB Ref ID: 26899 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1988, no author, 

December 1990: SRDB Ref ID: 26900 

• Radiation Exposures Report for DOE and DOE Contractor Employees – 1989, no author, 

December 1992: SRDB Ref ID: 16122 

• Recycled Uranium mass balance project Y-12 national security complex site report, Y/LB-16,036, 

Rev. 1, Y-12 National Security Complex, December 2000; SRDB Ref ID: 16500 

• Report of Survey of Oak Ridge Isotope Enrichment (Calutron) Facility Building 9204-3, U. S. 

Department of Energy Office of Environmental Management & Office of Nuclear Energy, May 5,

2000; SRDB Ref ID: 17691 

• Characterization of the Radioactive Material Inventory in the Building 9204-3 Actinide Facility, 

Oak Ridge National Laboratory, Walker, May 8, 2012; SRDB Ref ID: 176792 

• Y-12 continues missions while focusing on environment, no author, no date; SRDB Ref ID:

176793 

5.0 Radiological Operations Relevant to the Class Evaluated by 

NIOSH

The following subsections summarize radiological operations at the Y-12 Plant from January 1, 1977 

to December 31, 1994 and the information available to NIOSH to characterize particular processes 

and radioactive source materials. From available sources, NIOSH has gathered process and source 

descriptions, information regarding the identity and quantities of each radionuclide of concern, and

information describing processes through which radiation exposures may have occurred and the 

physical environment in which they may have occurred. The information included within this 

evaluation report is intended only to be a summary of available information. 
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5.1 Y-12 Plant and Process Description

ATTRIBUTION: Section 5.1 was completed by ORAU Team Subject Expert Joe Guido, MJW 

Corporation. All conclusions drawn from the data presented were peer-reviewed by the individuals 

listed on the cover page. The rationales for all conclusions in subsequent sections of this document 

related to Y-12 plant and process descriptions are explained in the associated text. 

The Y-12 Plant is located in Oak Ridge, Tennessee on an 811-acre (0.67-mile wide by 3.2-mile long) 

site. At its peak, the Y-12 Plant employed approximately 22,000 workers (ORAUT-TKBS-0014-2). 

In later years (including the period under evaluation, January 1, 1977 through December 31, 1994), 

downsizing had resulted in there being approximately 5733 employees by June 1998 (Pepper, 2000, 

PDF p. 56). The following subsections summarize the radiological operations at the Y-12 Plant from 

January 1, 1977 through December 31, 1994. 

Y-12 Plant operations discussed in this section are divided into the following functional areas: 

• Uranium Processes

• Thorium Processes

• Isotopes Group Activities 

5.1.1 Y-12 Key Uranium Processes

Table 5-1 summarizes the key uranium processes, buildings, and dates of operation relevant for the 

evaluation period of this petition (1977-1994) (Oak Ridge, 1999, PDF p. 171; Oliver, 2003; Oliver, 

2007).

Table 5-1: Key Uranium Operations

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 natural 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. 

1950s-1990s
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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 enrichments. 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 

high-efficiency 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
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5.1.2 Y-12 Thorium Processes

Y-12’s involvement in the production of thorium metal shapes began as a pilot program in 1959. It 

was a continuation of work previously performed at the Bureau of Mines in Albany, Oregon. Bureau 

of Mines operations included arc-melting, forging, rolling, and forming of thorium (Hibbs, 1961). 

Y-12 completed its initial order in October 1959. Table 5-2 lists the Y-12 buildings involved in these 

initial thorium activities.

Table 5-2: Y-12 Buildings Involved in Initial Thorium Operations

Building No. Thorium Operation(s)

9202 Arc-melting

Double hammer forging

Machining to final dimensions

Annealing

Development

9766 Machining

9215 Cold rolling

Drawing to shape (hydroforming)

9201-5 Pellet/scrap preparation

Arc-melting

Crop and trim machining

Sawing

9204-4 Mold press sintering 

Ingot forging

Annealing after first cold roll

Final inspection/assembly

9201-1 Ingot canning

9206 Cleaning and final plating

9902 Storage

9995 Storage

Source: Hibbs, 1960; Hibbs, 1961; Thorium Machining, 1960, RCO/TR-013, 

2001, PDF pp. 11-12

Thorium activities were expanded in the 1960s with facilities dedicated to these operations 

constructed in Building 9201-5 and 9204-2E. Other areas with thorium operations included Building 

9204-4 (mold press, ingot forging), Building 9201-1 (canning ingots), and Building 9206 (cleaning

and final plating). Buildings 9902 and 9995 were also used for thorium storage (RCO/TR-013, 2001, 

PDF pp. 11-12). Y-12 contracted with other companies for thorium pellets and then pressed the metal 

into electrodes; subsequently, two arc-meltings were performed (Thorium Flow Chart, 1963, PDF p. 

1).

The primary thorium process at Y-12 is consumable-electrode arc-melting in which the material to be 

cast serves as one electrode of an electric-arc gap, and the heat of the arc melts the electrode. The 

opposite electrode is in a water-cooled crucible in which the molten metal solidifies. The consumable 

electrode is gradually lowered to maintain the proper arc gap, resulting in the melting of the 

consumable electrode and the casting of an ingot in the water-cooled crucible. Volatile impurities 

tend to move toward the cold walls of the crucible where they may be removed by light machining of 

the ingot (Cofield, 1961). 
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After arc-melting, which removed most of the impurities, the thorium metal was then pressed, rolled, 

and formed or machined. The metal scraps were salvaged and pressed into electrodes for the 

arc-melting process. Figure 5-1 shows a summary of the Y-12 thorium production-scale activities. 

Figure 5-1: Thorium Flow Chart for Contamination Control

Source: Thorium Flow Chart, 1963
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An interview with a former worker indicated that the major activities involving thorium continued 

through the mid-1970s, after which the demand for thorium components diminished. He indicated 

that from 1960 through 1977, metric tons of thorium were processed at Y-12. Processing included 

molding/pressing of thorium pellets, arc-melting, and machining. In 1975, the major arc-melting 

campaign stopped (due to the SALT II treaty ending of the W-71 weapons program) (Personal 

Communication, 2018e). Another interview of a Y-12 employee who worked in [redacted] indicated 

that he was aware of thorium work in 1974; however, once the W-71 weapons program was 

completed there was not much need for thorium and he did not know of any additional thorium work 

(Personal Communication, 2018d). A February 25, 1969 document states: 

The thorium monitoring program in the arc melt area has been discontinued and added back to 

monitor for uranium. No changes have been made in the thorium program in the chip and press 

areas at this time. Tentative plans call for elimination of these area programs around July after 

complete phase out and decontamination (Thorium Melt, 1969).

One employee that NIOSH interviewed indicated that, after the cessation of major thorium operations 

in 1975, a small amount of thorium processing (including arc-melting) continued for the 

refurbishment of parts through 1989 (Personal Communication, 2018e). 

From September 1994 through August 1998, the Y-12 plant was placed in a stand-down mode 

(Eckerman, 1999), which effectively stopped all routine work (and chronic exposure potential) in the 

process areas. After this stand-down, area controls were put in place to restrict access, and a small 

amount of special-project thorium work (including arc-melting for the development of detector plates) 

was performed until 1999 (Personal Communication, 2018e). 

On December 8, 1999, there was a catastrophic event involving depleted uranium operations with a 

Y-12 furnace, which injured multiple employees (NaK Accident, 2000). As a result of this incident, 

all arc-melting activities (which were primarily depleted uranium but did include the special projects 

mentioned above) were suspended (Personal Communication, 2018e). 

5.1.3 Isotopes Group Activities

Y-12 facilities were used by the ORNL Isotopes Group for isotope production, separation, and 

purification. Although both radioactive and stable materials were processed, this evaluation only 

focuses on radioactive isotopes. Facilities used by the Isotopes Group on the Y-12 campus include 

calutrons located in Building 9204-3, the 86-inch cyclotron located in Building 9201-2, and the 

conversion laboratory located in Building 9204-3. Operations at all three of these facilities are 

summarized below. 

Calutron Facility (Building 9204-3)

Calutron operations at Y-12 extend back to the early 1940s when they were used for uranium 

enrichment. After that effort, small portions of the existing calutrons were used by the Isotopes 

Group (and their predecessor, the Electronuclear Research Division) for the separation of both 

radioactive and stable materials. In 1962, a containment facility was built in Building 9204-3 that 

included separations areas, chemical processing areas, a change room, and a locker room. One 

track in Building 9204-3 was divided into four segments, and eight calutrons were isolated within a 

containment facility for radioisotope separations. Two of these calutrons were designated for 

plutonium and four for uranium production. The actinide area operated continuously from 1962 
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until the mid-1970s when it was put on standby. The facility was operated again in the late-1970s 

for the separation of Pu-242; it was again placed on standby in 1980 (ORNL, 1995; Wilcox, 2001). 

86-inch Cyclotron (Building 9201-2) 

The 86-inch cyclotron was operated almost constantly from 1950 for research, development, and as a 

production facility for medical radioisotopes; it was shut down in 1983 (Kerr, 1992; Kerr, 2004). 

From its earliest operations, this cyclotron was often run for hundreds of hours before shutdown, 

which was usually necessary only due to target limitations (CCCC, 1951). The device was used as a 

resource by practically all of the ORNL divisions, including Aircraft Nuclear Propulsion, Biology, 

Chemistry, Health Physics (HP), Operations, Physics, and Electronuclear Research. It was also used

substantially for projects at the Oak Ridge Institute of Nuclear Studies, which later became ORAU 

(Livingston, 1952). 

Conversion Lab (Chemical Processing Area of Building 9201-3) 

The Conversion Lab was a radiochemistry facility located in the containment area in Building 9204-3. 

Its activities included preparation of calutron feed materials, radiochemical separations, source 

preparation, and radioassay. Radionuclides handled in the Conversion Lab included materials from 

the calutrons and from ORNL. 

5.1.4 Weapons Assembly and Disassembly 

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 because the parts for assembly were essentially clad or otherwise sealed. Dosimeters

were worn on company-issued work clothing. 

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 unlikely. In addition, when maintenance personnel were needed in the area, they 

were always required to wear personal dosimeters.
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5.2 Radiological Exposure Sources from the Y-12 Plant Operations

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

Y-12 Plant class under evaluation. During Y-12’s operational radiation period from January 1, 1977 

through December 31, 1994, the primary source of potential exposure was from uranium facility 

weapons-related work. Potential exposures also existed from thorium work activities involving the 

production of thorium metal shapes, and other radionuclides produced and handled by the Isotopes 

Group.

5.2.1 Internal Radiological Exposure Sources from the Y-12 Plant Operations

This section addresses exposures to alpha-emitting radionuclides. The primary sources of potential 

internally-deposited radioactivity for Y-12 employees during the operational period were inhalation 

and ingestion of uranium and thorium activity occurring during uranium and thorium metal operations 

and legacy contamination remaining because of those operations.

5.2.1.1 Uranium

The principal source of internal radiation doses for members of the evaluated class was airborne 

uranium particulate material. This dust could be inhaled by individuals and then be deposited in the

respiratory tract. The dust would also settle onto surfaces and be available for re-suspension back 

into the air where it could be inhaled or ingested in the body by transfer from contaminated surfaces 

via hand to mouth.

Trace quantities of plutonium, neptunium-237, and technetium-99 were introduced through the 

processing of recycled uranium. Contributions from these nuclides are detailed in ORAUT-TKBS0014-5.

5.2.1.2 Thorium

Another source of internal radiation doses for members of the evaluated class was airborne thorium 

particulate material. This dust could be inhaled by individuals and then be deposited in the respiratory 

tract. The dust would also settle onto surfaces and be available for re-suspension back into the air 

where it could be inhaled or ingested in the body by transfer from contaminated surfaces via hand to 

mouth.

Undisturbed, the Th-232 and Th-228 activity reach a state of equilibrium wherein the radiological 

activity of Th-232 and Th-228 are equal. Because of the half-lives of the nuclides in the thorium 

chain, removal of the Ra-228 component will result in a decrease in the Th-228 activity for a period of 

time, during which the Ra-228 activity will increase, as shown in Figure 5-2 (NIOSH, 2018, PDF p.

16).
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Figure 5-2: Activities in a Purified Thorium Sample

Source: West, 1965

The casting of ingots by consumable-electrode arc-melting was expected to produce a much greater 

disruption of the thorium decay chain than the other treatments such as acid "pickling," machining, 

forging, or shaping. 

The effects of arc-melting were well studied by the health physics staff at Y-12 (Cofield, 1960; 

Cofield, 1961; West 1961a; West, 1961b; West, 1965; West 1977) who learned that arc-melting of 

thorium effectively removes the radium and other daughters from thorium, but all of the daughters 

except Ra-228 and Ac-228 return very quickly and remain with the Th-228 present. In addition, the 

arc-melting of thorium releases large quantities of Ra-228. For example, in the casting of a typical 

200-kg ingot of thorium, about 9.6 mCi of Ra-228 will be removed with more than half or at least 5 

mCi of this radioisotope vaporized completely out of the ingot. The 5 mCi of Ra-228 becomes more 

of a radiological hazard as separated material than it was when distributed within the 200 kg of metal 

(NIOSH, 2018, PDF p. 18). 

5.2.1.3 Radionuclides Produced and/or Handled by the Isotopes Group 

The Isotopes Group produced and/or handled 213 individual radionuclides at facilities on both the 

ORNL X-10 footprint and that of Y-12. Y-12 separations facilities could have been used to process 

materials produced at X-10 reactors. Material transfers between Isotopes Group facilities located at

Y-12 and ORNL X-10 were common. For this reason, with some exceptions, it can be generally
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assumed that all of the materials detailed in ORAUT-RPRT-0090 may have been present in Isotopes 

Group facilities on the Y-12 campus (particularly the Conversion Laboratory). A detailed list of the 

radionuclides handled is contained in Table 6-3 of ORAUT-RPRT-0090. Radiological properties of 

these materials are detailed in Attachment B of that same document.

5.2.2 External Radiological Exposure Sources from the Y-12 Plant Operations

The potential for external radiation dose existed at the Y-12 Plant facility in all areas where 

radioactive materials were handled or stored. Based on the site operations, sources of external 

exposure included photon and beta radiation emitted from the thorium and uranium metal processed at 

the site. Due to the type of metal being processed, neutron exposure was not significant, as examined 

below. 

The processing of thorium metals at Y-12 began in the late 1950s or early 1960s (ORAUT-TKBS0014-2, West, 1965; Wilcox, 2001). In general, the same Y-12 facilities were involved in the 

processing and fabrication of both thorium and DU metals (ORAUT-TKBS-0014-2; McLendon, 

1963; McRee, 1965). The external beta/photon doses to the thorium workers were found to be lower 

than or at the same order of magnitude as those doses to depleted-uranium workers (West, 1965, PDF 

p. 27). 

5.2.2.1 Photon 

Though less of an exposure potential than internal exposure, significant external exposure potential 

existed at times in specific locations or while engaged in certain 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 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) (NIOSH, 2006, 

PDF p. 21). 

The U-235 and U-238 contained in Y-12 uranium materials are primarily alpha-emitters. However, 

U-235 does emit a 185-KeV photon in 54% of its decays. 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 decay products of U-238 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 (NIOSH, 

2006, PDF pp. 20-21). 

The largest workplace exposures at Y-12 have historically occurred in DU process areas (Henderson, 

1991). In the foundry and forming areas, workers handled both large and small pieces of DU metal; 

however, the workers were not typically in close contact with the material for long periods of time 

(Ashley, 1995, PDF p. 10). Large parts were lifted with mechanical assistance and the workers 

usually remained 2-3 feet from the material. Smaller parts might be loaded by hand but the operator 

then moves to a control center several feet away, where the operator remains for the majority of the 

time spent working with the material (Ashley, 1995, PDF p. 10). Similar workplace conditions are 

found in the facilities of the Ultrasonic Testing Group of the Y-12 Quality Assurance department 

(Ashley, 1995, PDF p. 11). In contrast, workers in the Machine Shops, Mechanical Properties 

Inspection Laboratories, Dimensional Inspection Group, and Radiographic Laboratories could spend a 
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considerable part of their time working in close contact to the material (less than 30 cm) for extended 

periods (Ashley, 1995, PDF p. 11). 

A concern with the workplace response of the Y-12 beta/gamma dosimeters involves workers who 

performed waist-level uranium handling of small metal objects in the DU areas (Henderson, 1991, 

PDF p. 46). A personnel dosimeter worn at the collar might underestimate both the Hp(0.07) and 

Hp(10) doses at the waist by a rather significant factor. Y-12 now instructs these workers to wear the 

dosimeters at the waist, but many workers might have worn them on the collar in the past. 

(Henderson 1991, PDF p. 47; ORAUT-TKBS-0014-6).

Photo emissions information on radionuclides handled at Isotopes Group facilities is discussed in 

detail in ORAUT-RPRT-0090 (Tables 7-4 and Attachment B). 

5.2.2.2 Beta

When uranium metal is melted, impurities can separate from the metal matrix. Differences in 

densities and melting points can then cause impurities to separate from the molten uranium metal and 

concentrate on the surfaces (i.e., Th-234, Pa-234m, decay products of U-238). The process then 

causes a high concentration of these beta-emitters on the surfaces of the cast ingot, increasing the 

surface beta dose. 

Beta emissions information on radionuclides handled at Isotopes Group facilities is discussed in detail 

in ORAUT-RPRT-0090 (Tables 7-4 and Attachment B). 

5.2.2.3 Neutron 

There are four buildings at Y-12 where the majority of the site’s neutron-emitters were present during 

the period under evaluation (1977 through 1994) (ORAUT-TKBS-0014-6, 2009, PDF p. 42): 

• Calibration Laboratory in Building 9983 

• Nondestructive Analysis Laboratory in Building 9720-5 

• HEU Storage Area in Building 9212 

• Cyclotron operations in Building 9201-2 

Calibration Facility (Building 9983) 

The Calibration Facility had encapsulated sources that produced neutrons by spontaneous fission in 

Cf-252 or by alpha particle reactions with boron or beryllium providing convenient sources of 

neutrons for a variety of applications. Known locations of such sources producing neutrons by alpha 

particle reactions are Buildings 9201-2, 9203, 9204-3, 9737, and 9983 (ORAUT-TKBS-0014-2, PDF

pp. 21-22). 

Once the handling procedures for an encapsulated neutron source were established, the services 

provided by the HP Department evolved into routine periodic checks. Instrumentation calibrations 

with Po-Be, Pu-Be, Am-Be, and Am-B sources were a standardized operation in that the majority of 

calibrations were made at one location and usually by the same operator. Any unusual operations or 

transfers involving encapsulated neutron sources were done under the supervision of the HP 

Department (ORAUT-TKBS-0014-6, PDF p. 31). 
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Nondestructive Analysis Laboratory (Building 9720-5) 

The Nondestructive Analysis Laboratory had Cf-252 sources that undergo spontaneous fission and 

create neutrons. These sources have been used for testing materials and recovery of highly-enriched 

uranium (HEU) from waste products. This laboratory contained instruments for the gamma and 

neutron monitoring of containers of solid wastes, gamma analysis of solution samples, and 

measurements of solution density (ORAUT-TKBS-0014-6, PDF p. 32-33). 

HEU Storage Area (Building 9212) 

The HEU Storage Area was another source of neutron exposure. Recycled uranium process streams 

involved the processing of other material forms. The potential for worker exposure to neutrons 

generated by (α,n) reactions in uranium compounds is not very high unless workers needed access

near containers of uranium-fluoride or uranium-oxide compounds, or near storage or processing areas 

with large quantities of those materials (ORAUT-TKBS-0014-6, PDF p. 33-34). 

Cyclotron Facility (Building 9201-2) 

The 86-in. cyclotron was another source of neutron exposure. The cyclotron was used 

primarily by ORNL Isotopes Group for production of medical radioisotopes until it was shut 

down permanently in 1983 (Kerr, 1992; Kerr, 2004). 

6.0 Summary of Available Monitoring Data for the Class Evaluated 

by NIOSH

The following subsections provide an overview of the state of the available internal and external 

monitoring data for the Y-12 class under evaluation.

External penetrating and shallow exposures to particulate and photon radiation were monitored using 

radiation-sensitive materials within personnel badges worn by workers. Detailed historical 

evaluations of the Y-12 gamma, neutron, and beta monitoring programs, including applicable 

radiation protection guidelines, can be found in the external dosimetry technical basis document for 

the Y-12 plant, ORAUT-TKBS-0014-6. 

Internal exposures to radionuclides were monitored by counting radioactive emissions in workers’ 

excreta (urine) and via air sampling. Routine in-vivo chest counting at Y-12 was not initiated until 

1961. Detailed historical evaluations of the Y-12 in-vivo, in-vitro, and air sampling monitoring 

programs including applicable radiation protection guidelines can be found in the internal dosimetry 

technical basis document for the Y-12 plant (ORAUT-TKBS-0014-5).

Radiological monitoring and controls at the Isotopes facilities on the Y-12 campus were managed 

and provided by ORNL (Redacted Name1, 2012; Redacted Name2, 2012). These operations were 

staffed and managed by ORNL X-10, with some Y-12 workers supporting operations. Records from 

1965 indicate that some construction support contract staff (Harrold Knudson Ferguson [HKF] at the 

time) were among the individuals monitored at the calutron facility (NIOSH, 2018). 
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6.1 Available Y-12 Plant Internal Monitoring Data

The subsections below address the availability of data related to uranium and thorium. Details 

regarding the various analyses used and the associated minimum detectable activities are presented in 

the Technical Basis Document for the Y-12 Plant-Occupational Internal Dose (ORAUT-TKBS-0014-

5).

6.1.1 Available Uranium Data 

ATTRIBUTION: Section 6.1.1 was completed by ORAU Team Subject Expert Joe Guido, MJW 

Corporation. All conclusions drawn from the data presented were peer-reviewed by the individuals 

listed on the cover page. The rationales for all conclusions in subsequent sections of this document 

related to available uranium data are explained in the associated text. 

Throughout the evaluation period, the Y-12 Plant monitored workers for exposure to uranium 

through both in-vivo (lung counting) and in-vitro (urinalysis) methods (ORAUT-TKBS-0014-5). 

The Y-12 Radiation Safety Manual instructions for frequency of urine monitoring stated: 

Sample at the frequency necessary to assure, with at least 95% confidence, that 95% of the 

individuals in a department have a quarterly average below the plant action limit (McLendon 

1963). 

Urinalysis sampling frequency was reviewed monthly and adjusted semiannually. Through 1990, 

lung counting was performed using a sodium iodide (NaI) scintillation detector system; thereafter, 

a high-purity germanium (HPGe) detector system was used. Samples were analyzed by either 

fluorometry or alpha-counting (after electro-deposition), depending on the enrichment of material 

to which the individual was exposed. 

NIOSH has uranium urine and lung data through 1988 from the CER datasets described in Section 

4.8. Table 6-1 below provides a summary of the data available from the CER. Note that the 

percentage-monitored data in Table 6-1 was determined by dividing the number of individuals 

monitored for each urine sampling and lung counting by the number of individuals monitored by 

external dosimetry (see Table 6-4). For the 1977-1988 time period, the number of individuals 

monitored for external dose is an approximation of the number of individuals working on the site 

based on the high frequency of external monitoring data observed for NOCTS claimants (for the 

period from 1977 through 1988, 91% of NOCTS claimants have external monitoring). Urine and 

lung-counting data are available for individual claimants within NOCTS with approximately 47% 

of claimants having internal monitoring data (see Section 4.4).
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Table 6-1: Summary of Available CER Data

Year No. of Urine 

Samples

No. of 

Individuals 

Monitored by 

Urine Sampling

Percent of 

Individuals 

Monitored by 

Urine Sampling

No. of Lung 

Count 

Measurements*

No. of 

Individuals 

Monitored by 

Lung 

Counting* **

Percent of 

Individuals 

Monitored by 

Lung 

Counting*

1977 3475 664 12% 1411 1061 20%

1978 3409 689 12% 1512 1173 21%

1979 3504 840 14% 1794 1362 23%

1980 3985 952 15% 1798 1366 22%

1981 4842 1004 16% 2091 1588 26%

1982 5836 1211 18% 3051 2264 33%

1983 5504 1313 19% 3149 2471 35%

1984 6389 1356 19% 3087 2350 33%

1985 6265 1296 17% 2960 2216 28%

1986 6629 1125 15% 2430 1674 23%

1987 6164 1043 15% 2131 1709 24%

1988 5559 1359 19% 3028 2130 29%

Total 61561 3675 30% 28442 4801 40%

* Cited value is for all lung counts performed (i.e., not limited to U).

** NOTE: The values in Columns 3 and 6 represent the number of unique individuals monitored during each specific year. 

The Total value in the last record in Column 6 does not represent the sum of the values in that column. It represents the 

actual number of unique individuals monitored from 1977-1988.

ORAUT obtained a set of lung count data in the form of a spreadsheet from Y-12 Internal Dosimetry 

department from its electronic record keeping system (Lung Count Spreadsheet, 1984–1995) (see 

Section 4.7). Table 6-2 summarizes the total number of uranium-related measurements by year. 

NIOSH was able to use the ‘analysis type’ (see Table 6-2) provided in the spreadsheet to identify 

uranium-related counts. There are 23,708 data points for uranium-related measurements for 4,652 

individuals available between 1977 and 1986. 

Table 6-2: Type Analysis Chart 

Type Analysis Elements Reported* Description**

0 None Background Runs

1 Enriched Uranium, Potassium, 

Cesium

U-235

3 Lead, Actinium, Potassium, Cesium Thorium

4 Total Uranium, Potassium, Cesium U-238 and U-235

6 Enriched Uranium, Lead, Actinium, 

Potassium, Cesium

Thorium and U-235

7 Enriched Uranium, Total Uranium, 

Lead, Actinium, Potassium, 

Cesium, Technetium

U-235 and Thorium

* “Elements Reported” column data from Batte, 1983

** “Description” column data from Detail File Layout, undated
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Table 6-3: Uranium-related Records 1977-1986

Year No. of Individuals*

No. of Uraniumrelated 

Measurements 

1977 1075 1431

1978 1176 1512

1979 1370 1808

1980 1368 1799

1981 1684 2252

1982 2284 3152

1983 2513 3227

1984 2397 3139

1985 2217 2960

1986 1672 2428

 Grand Total 4652 23708

* NOTE: The values in Column 2 represent the number of unique 

individuals with U-related measurements during each specific year. 

The Grand Total value in the last record in Column 2 does not 

represent the sum of the values in that column. It represents the

actual number of unique individuals with U-related measurements 

from 1977-1988.

6.1.2 Available Thorium Data

ATTRIBUTION: Section 6.1.2 was completed by ORAU Team Subject Expert Joe Guido, MJW 

Corporation. All conclusions drawn from the data presented were peer-reviewed by the individuals 

listed on the cover page. The rationales for all conclusions in subsequent sections of this document 

related to available thorium data are explained in the associated text. 

Thorium-related lung count data are available from several data sources representing different parts 

of the evaluation period (January 1, 1977 through December 31, 1994). These measurements were 

performed at the Y-12 in-vivo counting facility using a NaI-based detector system. The available 

thorium-related lung count data sources include:

• Thorium lung-count data from 1958 through 1982 from a Y-12 spreadsheet (Thorium Lung 

Counts, 2005). There are 518 thorium lung counts from 1979 through 1982 in mass units (i.e., 

mg). 

• Ac-228 and Pb-212 data associated with analysis sequence codes 3, 6, and 7 (which included 

thorium, as indicated in Table 6-2 above) performed from 1979-1986 and contained in the 

excerpt file from the Y-12 electronic records system (described in Section 4.7). There are 1007 

counts with Ac-228 and Pb-212 results in activity units (i.e. nCi) for 808 individuals. 

• Between 1979 and 1982, monitoring data for thorium are available in NOCTS claimant files and 

are reported as ‘Th’ in units of ‘mg’. These files do not contain data specific to “Th” between 

1982 and 1986. Figure 6-1 shows the number of thorium counts available for each year 

(documented in mg units) from 1979 through 1982, the number of Ac-228/Pb-212 counts 

(documented in nCi) through 1986, and the number of thorium counts contained within a 

collection of NOCTS files for Y-12 claimants. Note that for the purpose of the chart, all 
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Ac-228/Pb-212 measurements were used (not just the ones assigned as Types 3, 6, and 7). This 

was done so that an accurate comparison can be made between the Ac-228/Pb-212 dataset and the 

Th(mg) dataset since the Th(mg) dataset did not contain the analysis type field. The large 

discrepancy between the Ac-228/Pb-212 dataset and the Th(mg) dataset in 1979 is due to the fact 

that the Ac-228/Pb-212 dataset only covers August – December of that year. For the NOCTS 

dataset, thorium lung-count data from all available Y-12 claims were compiled up to NOCTS 

claim number 48453, comprising 2105 individual claims (NIOSH, 2018, PDF p. 25). 

Figure 6-1: Thorium Lung Count Measurements

NIOSH cannot use source term data to determine internal exposures because such data are not 

available to NIOSH (NIOSH, 2018, PDF pp. 31-33).

NIOSH continues to work with the Y-12 site to receive post-1986 activity-based thorium progeny data 

(i.e., Ac-228 and Pb-212) that may allow NIOSH to estimate the maximum internal potential exposure 

from thorium to members of the evaluated class during the period from January 1, 1987 through 

December 31, 1994. Therefore, NIOSH is reserving its evaluation of internal exposure from thorium 

for the period from January 1, 1987 through December 31, 1994 until activity-based thorium progeny 

data are available.
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Available Thorium-related Air Sampling Data

NIOSH received a spreadsheet from Y-12 (Thorium Air Samples, 1960-76) containing the results 

(in dpm/m3) of 79,997 air samples specific to thorium operations that span the period from 1960 

through 1976. These air sample results appear to have been fixed sample locations based on the 

presence of assigned location IDs with each result (NIOSH, 2018, PDF p. 22). 

6.2 Available Y-12 Plant External Monitoring Data

NIOSH has access to the photon, beta, and neutron external dosimetry results, as well as other 

supporting data representing Y-12 site operations throughout the time period under evaluation in this 

report (January 1, 1977 through December 31, 1994). Details regarding the various analyses used, 

and the associated minimum detectable doses, are presented in ORAUT-TKBS-0014-6. In addition, 

NIOSH has external dosimetry data through 1988 from the CER datasets described in Section 4.8. 

Table 6-4 below provides a summary of the data available from CER. 

Table 6-4: Summary of Available CER (External Dose) Data

Year No. of External Dose 

Measurements

No. of Individuals Monitored 

for External Dose

1977 19757 5361

1978 20162 5573

1979 21239 5964

1980 16877 6156

1981 8049 6157

1982 8855 6779

1983 8638 7074

1984 8895 7185

1985 9599 7797

1986 9318 7345

1987 8132 7173

1988 8757 7317

Total 148278 12058

* NOTE: The values in Column 3 represent the number of unique individuals 

monitored during each specific year. The Total value in the last record in Column 3 

does not represent the sum of the values in that column. It represents the actual 

number of unique individuals monitored from 1977-1988.

To assess potential external dose to unmonitored employees, NIOSH developed a co-worker dose 

distribution model, ORAUT-OTIB-0064, using the external dose data contained in CER. Summaries

of the monitoring techniques and typical exchange frequencies for the various personnel dosimeters 

used at the Y-12 Plant during different periods of time are provided in ORAUT-TKBS-0014-06. 
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Detailed information on external monitoring provided by ORNL X-10 (which would be applicable to 

individuals working at Isotopes facilities on the Y-12 campus) is presented in the Technical Basis 

Document for the ORNL Site - Occupational External Dose (ORAUT-TKBS-0012-6) and External 

Coworker Dosimetry Data for the X-10 Site (ORAUT-OTIB-0021).

Details regarding the various analyses used and the associated minimum detectable doses are 

presented in the Technical Basis Document for the Y-12 Plant-Occupational External Dose (ORAUTTKBS-0014-6).

7.0 Feasibility of Dose Reconstruction for the Class Evaluated by 

NIOSH

The feasibility determination/s for the class of employees under evaluation in this report is governed

by both EEOICPA and 42 C.F.R. § 83.13(c)(1). Under that Act and rule, NIOSH must establish 

whether or not it has access to sufficient information either to 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 to estimate the radiation doses to

members of the class more precisely than a maximum dose estimate. If NIOSH has access to 

sufficient information for either case, NIOSH would then determine that it would be feasible to 

conduct dose reconstructions.

In determining feasibility, NIOSH begins by evaluating whether current or completed NIOSH dose 

reconstructions demonstrate the feasibility of estimating with sufficient accuracy the potential 

radiation exposures of the class. If the conclusion is one of infeasibility, NIOSH systematically 

evaluates the sufficiency of different types of monitoring data, process and source or source term data, 

which together or individually might ensure that NIOSH can estimate either the maximum doses that 

members of the class might have incurred, or more precise quantities that reflect the variability of 

exposures experienced by groups or individual members of the class as summarized in Section 3.2. 

This approach is discussed in NIOSH’s SEC Petition Evaluation Internal Procedures, which are

available on the NIOSH Radiation Dose Reconstruction Program webpage. 

The next four major subsections of this evaluation report examine:

• The sufficiency and reliability of the available data. (Section 7.1)

• The feasibility of reconstructing internal radiation doses. (Section 7.2)

• The feasibility of reconstructing external radiation doses. (Section 7.3)

• The bases for petition SEC-00250 as submitted by the petitioner. (Section 7.4)

7.1 Pedigree of Y-12 Plant Data

This subsection answers questions that need to be asked before performing a feasibility evaluation. 

Data Pedigree addresses the background, history, and origin of the data. It requires looking at site 

methodologies that may have changed over time; primary versus secondary data sources and whether 

they match; and whether data are internally consistent. All these issues form the bedrock of the 

researcher’s confidence and later conclusions about the data’s quality, credibility, reliability, 

representativeness, and sufficiency for determining the feasibility of dose reconstruction. The

feasibility evaluation presupposes that data pedigree issues have been settled.
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In addition, as part of evaluating the pedigree and sufficiency of Y-12 internal and external monitoring 

data, NIOSH evaluated the following:

• The overall suitability of Y-12’s internal and external monitoring program

• Internal and external exposure sources and exposure potential of the workforce

• Internal and external exposure monitoring data availability and quality

• Internal and external reviews and assessments of Y-12 monitoring data

• Doses assigned by Y-12

With the exception of a current need to retrieve thorium lung-count data for the period from January 1, 

1987 through December 31, 1994, NIOSH’s evaluation concludes that data of sufficient quality, 

credibility, reliability, and representativeness are available to reconstruct Y-12 occupational exposures 

from August 1, 1979 through December 31, 1986. Y-12’s radiological source terms and monitoring 

program were well-documented during the period under evaluation and the relevant documents have 

been extensively captured and reviewed for appropriateness. In addition, much of the available 

internal and external monitoring data are available as original results or images of original results and, 

as such, can be considered “primary” data sources. Available electronic datasets, though not always 

true primary data, have undergone extensive QA/QC and verification processes by other organizations 

such as the Oak Ridge Associated Universities’ (ORAU) Center for Epidemiological Research group. 

7.1.1 Internal Monitoring Data Pedigree Review

The following paragraphs briefly summarize the pedigree determinations (and conclusions regarding 

sufficiency for dose reconstruction) of several types of internal monitoring data captured or made 

available to NIOSH over the course of this evaluation. Additional details regarding these data can be 

found in Section 6.1. 

Y-12 urinalysis data for the period under evaluation are available to NIOSH from multiple data 

sources, including NOCTS and ORAU’s CER database for uranium (see Section 6.1). There is a 

sufficient quantity of good pedigree data for uranium analysis using ORAU CER data for the 

evaluated period up through 1988. This is evidenced in the co-worker analysis presented in Appendix 

B of ORAUT-TKBS-0014-05 and within ORAUT-OTIB-0075-01. This dataset was developed by the 

ORAU Center for Epidemiologic Research for use in epidemiology studies (Watkins, 1993) and has 

undergone detailed verification of its integrity. This same data source was used for uranium analysis 

for the SEC-00028 Y-12 evaluation report (NIOSH, 2006) and it is of sufficient pedigree to bound 

uranium doses for this evaluation (SEC-00250).

NIOSH has determined that the available in-vivo monitoring data for thorium (i.e., lung counts) are

insufficient to bound doses for the proposed class during the period from January 1, 1977 through July 

31, 1979. This is due to these lung-count data being reported in terms of mg of thorium versus the 

required Pb-212 and Ac-228 activity. As such, NIOSH does not have the ability to use these lungcount data to determine the associated exposures to thorium-232, thorium-228, and radium-228 with 

sufficient accuracy during this specific period; i.e., the current infeasibility for thorium is not a data 

pedigree issue.
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For the period starting in August 1979, NIOSH has obtained a useful set of lung-count data from the 

Y-12 Internal Dosimetry Department’s electronic record-keeping system. Within this dataset, there 

are 1007 thorium-related measurements of Ac-228 and Pb-212 by year available for 512 individuals 

from August 1979 through December 31, 1986. These data have been determined to be of sufficient 

pedigree to be used for bounding internal thorium doses from August 1, 1979 through December 31, 

1986.

7.1.2 External Monitoring Data Pedigree Review

The following paragraphs briefly summarize the pedigree (and conclusions regarding sufficiency for 

dose reconstruction) of external monitoring datasets captured or made available to NIOSH over the 

course of this evaluation. Details regarding these data, such as monitoring devices used, analyses 

performed, data sources, and the quantity of available data can be found in Section 6.2 of this report 

and in ORAUT-TKBS-014-6.

There are sufficient high-quality external dosimetry data available to NIOSH for reconstructing 

doses for the class under evaluation. These data exist as primary data records or images of primary 

data and/or reside in electronic databases that have undergone quality control verification processes. 

The volume of data results from nearly all workers having been monitored for external exposures 

annually (at least) during the evaluation period (January 1, 1977 through December 31, 1994). 

Workers identified as having greater external exposure potential were monitored quarterly (West, 

1993; Souleyrette, 2003, PDF p. 5). The frequency and availability of Y-12 external monitoring data 

are further evidenced via EEOICPA claims-processing results. As shown in Table 4-1, of the 3,615 

claimants who worked within the SEC-00250 evaluation timeframe, external dosimetry records have 

been supplied for 3,267 of these workers (90%).

NIOSH has also captured information indicating that the external exposure data were obtained from 

badges with known and sufficient performance characteristics. Furthermore, the badges were 

calibrated using sources appropriate for the radiation fields likely to exist at the site during the 

evaluation timeframe (ORAUT-TKBS-014-6). 

Based on NIOSH’s assessment of the Y-12 external dosimetry program, the results of its extensive 

data capture efforts, document reviews, and interviews with Y-12 personnel, NIOSH concludes that 

Y-12’s external monitoring data pedigree is sufficient to support bounding all potential external 

doses for the class under evaluation (January 1, 1977 through December 31, 1994).

7.2 Evaluation of Bounding Internal Radiation Doses at Y-12 Plant 

The principal source of internal radiation doses for members of the class under evaluation was 

airborne uranium or thorium particulate material. The following subsections address the ability to 

bound internal doses, methods for bounding doses, and the feasibility of internal dose 

reconstruction.

7.2.1 Evaluation of Bounding Process-Related Internal Doses

The following subsections summarize the extent and limitations of information available for 

reconstructing process-related internal doses of members of the class under evaluation.
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7.2.1.1 Urinalysis Information and Available Data 

Urinalysis data for uranium are available to NIOSH for the period under evaluation (January 1, 1977 

through December 31, 1994) from NOCTS and from ORAU’s CER database. Based on information 

in the CER database, monitoring data are available from 61,561 uranium urine samples collected 

between 1977 and 1988; approximately 30% of the site population was monitored for uranium intakes 

by urinalysis each year during this period (see Table 6-1). The ORAU CER database was used by the 

ORAUT to develop a co-worker model that covers the period 1976 through 1988. 

No urinalysis data are available specific to thorium.

7.2.1.2 Lung Counting Information and Available Data 

Lung counting data for uranium are available to NIOSH for the entire period under evaluation 

(January 1, 1977 through December 31, 1994) from the Y-12 dosimetry database extract (as 

described in Section 4.7), from NOCTS, and from ORAU’s CER database. 

NIOSH was able to use the ‘analysis type’ (as shown in Table 6-2) provided in the spreadsheet 

containing lung-count data to identify Pb-212 and Ac-228 results within thorium-related lung counts 

(e.g., analysis types 3, 6, and 7) (Lung Count Spreadsheet, 1984–1995). The total number of thoriumrelated measurements of Ac-228 and Pb-212 by year is summarized below in Table 7-1. One 

thousand-seven (1007) data points for thorium counts containing Pb-212 and Ac-228 data are 

available for the time period between August 1979 and December 1986. 

Table 7-1: Thorium Records 1979-1986

Year No. of Individuals** No. of Ac/Pb Measurements 

Used in Analysis

1979* 43 55

1980 110 128

1981 142 208

1982 83 179

1983 130 166

1984 87 89

1985 83 84

1986 95 98

Grand Total 512 1007

* Data starts in August 1979

** NOTE: The values in Column 2 represent the number of unique individuals 

monitored during each specific year. The Total value in the last record in 

Column 2 does not represent the sum of the values in that column. It 

represents the actual number of unique individuals monitored from 1979-

1986.

NIOSH is currently working with the Y-12 site to receive post-1986 activity-based thorium 

progeny data (i.e., Ac-228 and Pb-212). 
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Thorium lung-count data are also available for the period 1977 through 1982. These data were 

received directly from Y-12 in spreadsheet form (Thorium Lung Counts, 2005). There are 772 

thorium lung counts from 1977 through 1982. All of these data are reported as total thorium in 

units of mass (mg). 

7.2.1.3 Airborne Levels

NIOSH reviewed the available site information describing process activities conducted during the 

period under evaluation. The air-monitoring program in-place during that time period emphasized 

sample collection in those process areas with higher potential for airborne contamination. In 

addition to general area airborne uranium concentration levels, there are data available from jobspecific breathing-zone air-sampling events.

Air-sampling data specific to thorium for the period under evaluation (January 1, 1977 through 

December 31, 1994) are not available to NIOSH.

7.2.2 Evaluation of Bounding Ambient Environmental Internal Doses

For workers who were monitored with the in-vitro or in-vivo bioassay program at Y-12, any ambient 

environmental exposures would have been accumulated with the occupational exposures. 

The Occupational Environmental Dose TBD (ORAUT-TKBS-0014-4) applies to workers who were 

not monitored for external or internal radiation exposure. The environmental internal dose is that 

which workers could have received from inhalation of radioactive materials while being outdoors on 

the Y-12 plant site during or shortly after airborne releases.

The Occupational Environmental Dose TBD provides a table of annual average airborne concentration 

and intake data for U-234/235 and U-238. An empirical relationship was developed using on-site 

measured air concentrations and estimated uranium release estimates. This approach circumvents the 

need for air-dispersion modeling by providing a direct relationship between uranium air 

concentrations and uranium releases (ORAUT-TKBS-0014-4, PDF p. 19). The intake values that can 

be used for bounding dose estimates are presented in Table D-6, “Maximum Uranium-234/235 and 

Uranium-238 Air Concentrations and Intakes”. This information should be sufficient to allow 

bounding of ambient environmental internal dose for all members of the class who were not 

monitored with internal radiation dosimetry (ORAUT-TKBS-0014-4).

7.2.3 Methods for Bounding Internal Dose at the Y-12 Plant

The following subsections summarize the methods for bounding internal dose from uranium and 

thorium at Y-12.

Principal sources of internal radiation for members of the evaluated class include inhalation and 

ingestion during processing operations related to uranium, thorium (and progeny), and calutroncyclotron-related radioisotopes. Based on the evaluation documented in ORAUT-RPRT-0090, 

Monitoring Feasibility Evaluation for Exotic Radionuclides Produced by the Oak Ridge National

Laboratory Isotopes Division, the ORNL X-10 monitoring program encompassed the wide range 

of radionuclides that were produced by the Isotopes Group, including those produced and handled 

at the Isotopes facilities located on the Y-12 campus.
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7.2.3.1 Methods for Analyzing Uranium Bioassay Data

For the evaluation period from January 1, 1977 through December 31, 1994, based on a review of 

DOE-provided records for claims and records in repositories such as the ORAU CER database 

(described in Section 6.1), uranium-monitoring data are available. The methodologies to interpret 

the available monitoring data for use in dose reconstruction are contained in ORAUT-TKBS0014-5. In addition, a co-worker study (also documented in ORAUT-TKBS-0014-5) is available 

for NIOSH to evaluate uranium intakes to unmonitored workers between 1977 and 1988.

The data presented in ORAUT-TKBS-0014-5 indicate a downward trend in intake quantities over 

time. This is consistent with the summary of uranium urinalysis data for 1987-1992 presented in 

the Quarterly Plant Health Physics Report for fourth-quarter 1992, which indicates a downward 

trend in the number of individuals exceeding the site administrative control level for uranium 

(Hunt, 1992). Therefore, NIOSH can use the co-worker data provided in ORAUT-TKBS-0014-5 

to provide a bounding estimate of uranium intake for unmonitored individuals from 1989 through 

1994.

7.2.3.2 Methods for Analyzing Thorium Bioassay Data

Prior to August 1979, NIOSH confirmed that the available thorium-monitoring data are presented in 

mass units of total thorium. As discussed in the SEC-00251 evaluation report (NIOSH, 2018), 

NIOSH does not have the necessary information to employ these data for reconstructing internal dose

to Th-228, Th-232, and Ra-228. For this reason, these data were not used in this current evaluation 

report. 

Thorium-related doses from August 1979 through December 1986 can be bounded using the lungcount data retrieved from the Y-12 Electronic Records System, as illustrated in Table 7-1. The Ac228 and Pb-212 data are used, as indicated in ORAUT-OTIB-0076, Guiding Reconstruction of Intakes 

of Thorium Resulting from Nuclear Weapons Programs.” In summary, intakes of thorium are 

evaluated using chest counts and DCAL (Dose and Risk Calculation) software computational methods 

to account for disequilibrium and independent kinetics. In addition, NIOSH uses methods (i.e., 

Integrated Modules for Bioassay Analysis [IMBA]) to make conservative assumptions when bounding 

doses. The assumptions include:

• Pb-212 and/or Ac-228 activities can be established.

• A two-separation thorium production process operated at Y-12 (Personal Communication, 

2018e); however, since the thorium may have been separated once before Y-12 received the 

thorium, three separations will be assumed (this is more claimant-friendly).

• Independent kinetics are considered when necessary. For example, when thorium decays to 

radium, the kinetics are not shared but based on biokinetic differences because they are 

different elements. However, when thorium decays to other progeny, the kinetics are shared or 

assumed the same. 

Generally, Ac-228 activity can be used to calculate the Ra-228 activity, and Pb-212 can be used to 

calculate the Th-228 activity, which can then be used to calculate the Th-232 activity. Alternatively, 

when Pb-212 activity data alone are available, a conservative estimate of Th-232 activity can be made. 
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Assuming Y-12’s thorium underwent three separations, this means that Th-232 has a 0.19:1 Th-228-

to-Th-232 ratio and that there are no significant changes to the mixture over time, and that the thorium 

mixtures did not initially contain Ra-228 (ORAUT-OTIB-0076, PDF pp. 12-13). NIOSH determined 

that the maximum Pb and Ac result in the Y-12 dataset were 0.7 nCi for Pb-212 and 0.66 nCi for 

Ac-228, which could be used in bounding or maximum-dose calculations.

As indicated in Section 6.2, NIOSH is currently working with the Y-12 site to receive post-1986 

activity-based thorium progeny data (i.e., Ac-228 and Pb-212). NIOSH is reserving its evaluation of 

internal exposure from thorium for the period from January 1, 1987 through December 31, 1994 until 

activity-based thorium progeny data are available.

7.2.4 Internal Dose Reconstruction Feasibility Conclusion

NIOSH has determined that in-vivo monitoring data for thorium (i.e., lung counts) are insufficient to 

support reconstructing internal doses for the January 1, 1977 through July 31, 1979 portion of the 

evaluated class. 

NIOSH has determined that there are sufficient activity-based Pb-212 and Ac-228 in-vivo monitoring 

data to allow NIOSH to determine the associated intakes of thorium-232, thorium-228, and 

radium-228 with sufficient accuracy for the period from August 1, 1979 through December 31, 1986.

NIOSH has determined that there are sufficient in-vivo and in-vitro monitoring data for uranium (i.e., 

lung counts and urinalysis) during the period from January 1, 1977 through December 31, 1994 to 

allow NIOSH to determine the potential intakes of uranium with sufficient accuracy.

NIOSH has determined that there are currently sufficient calutron-cyclotron-related radioisotope data 

to estimate the maximum internal potential exposure to members of the evaluated class during the 

period from January 1, 1977 through December 31, 1994 for Isotopes Group workers on the Y-12 

campus based on the evaluation contained in ORAUT-RPRT-0090.

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 1, 1977 through July 31, 1979, but who do not qualify for 

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

7.3 Evaluation of Bounding External Radiation Doses at Y-12 Plant

The principal sources of external radiation doses for members of the evaluated class were uranium, 

thorium, calutron, and cyclotron operations (NIOSH, 2006). 

The following subsections address the ability to bound external doses, methods for bounding doses, 

and the feasibility of external radiation dose reconstruction.
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7.3.1 Evaluation of Bounding Process-Related External Doses

NIOSH has access to the photon, beta, and neutron external dosimetry results, as well as other 

supporting data representing Y-12 site operations throughout the time period under evaluation in this 

report. Details regarding the various analyses used, and the associated minimum detectable doses, are 

presented in ORAUT-TKBS-0014-6.

Photon

The external dosimetry data are sufficient to perform bounding dose reconstructions for photon 

exposures from all external gamma and X-ray sources that were present at Y-12 for all workers in the 

evaluated class. External radiation exposure data have been provided for claimants employed during 

the entire period under evaluation. In addition, the NIOSH has developed a co-worker study based on 

Y-12 external monitoring data (ORAUT-OTIB-0064).

Beta

The external dosimetry data are sufficient to perform bounding dose reconstructions for beta 

exposures from all sources that were present at Y-12 for all workers in the evaluated class. External 

radiation exposure data have been provided for claimants employed during the entire period under 

evaluation. In addition, the NIOSH has developed a co-worker study based on Y-12 external 

monitoring data (ORAUT-OTIB-0064).

Records of the external radiation dose to the extremities (hands and forearms) are also available for 

some individual workers who handled uranium metals. The so-called extremity personnel monitors 

for a worker’s hands consisted of finger rings containing photographic film from 1952 to 1980, and 

finger rings or wristbands containing thermoluminescent dosimeter (TLD) chips after 1980 (ORAUTTKBS-0014-6, PDF, p. 12).

Neutron

The external dosimetry data are sufficient to perform bounding dose reconstructions for neutron 

exposures from all sources that were present at Y-12 for all workers in the evaluated class. Neutron 

exposures have been monitored at Y-12 since 1961 and continued for the duration of the period under 

evaluation, with the resulting data available in personnel files. During the period from January 1, 

1977 through December 31, 1994, there were three Y-12 buildings where the majority of neutronemitters were present: the Calibration Laboratory in Building 9983, the Nondestructive Analysis 

Laboratory in Building 9720-5, and the Enriched Uranium Storage Areas in Building 9212 (ORAUTTKBS-0014-6, PDF p. 42). Radiation dosimetry was required for all workers entering such areas. If

there is a need to estimate neutron exposures for an unmonitored worker, ORAUT-TKBS-0014-6 

provides a protocol.

A review of DOE-provided records for claims confirms that monitoring records have been present in 

employee files The missed dose and bias/uncertainty factors derived in ORAUT-TKBS-0014-6 

should be applied. With these adjustments, the available data are sufficient to establish a bounding 

neutron dose estimate for the entire class under evaluation. 
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7.3.2 Evaluation of Bounding Ambient Environmental External Doses

Ambient external environmental monitoring data are available for the period from 1959 to beyond the 

end of the period under evaluation. NIOSH determined that the results of the 1987 outdoor scoping 

survey could be used for estimating external exposures for all years from 1948 to 2002. For this 

analysis, the highest exposure reading from either the scan or the direct measurement presented in the 

scoping survey was used. This approach presented the most conservative method of estimating 

exposures and ensures that areas of high exposure levels within each grid were included in the 

site-wide average. An evaluation of the ambient external radiation exposures is discussed in Section 

4.5.4 of ORAUT-TKBS-0014-4. The values provided in Table 4.4.4-1 of ORAUT-TKBS-0014-4 are 

sufficiently bounding for occupational exposures and could be used for unmonitored workers. 

However, the availability of personnel monitoring data obviates the need for area monitoring data as a 

substitute (ORAUT-TKBS-0014-4).

7.3.3 Y-12 Plant Occupational X-Ray Examinations

Y-12 medical X-rays were provided by the Y-12 Medical X-ray Department since February 1945 and 

therefore covered the SEC-00250 period under evaluation, January 1, 1977 through December 31, 

1994. The medical practices used at Y-12 are assumed to have followed the adoption of standards of 

radiology practice to minimize dose to the patient as technology improved. The type of medical X-ray 

equipment used, the frequency of X-rays (annual or less) by department, and techniques employed for 

all relevant projections and organ radiation doses over the Y-12 plant history are presented in 

ORAUT-TKBS-0014-3. Consistent with prior NIOSH evaluations, NIOSH concludes that it is 

feasible to reconstruct the occupational medical dose for Y-12 employees with sufficient accuracy 

during the period under evaluation.

7.3.4 Methods for Bounding External Dose at Y-12 Plant

NIOSH has an established protocol for assessing external exposure when performing dose 

reconstructions (these protocol steps are discussed in the following subsections):

• Photon Dose

• Beta Dose

• Neutron Dose

• Medical X-ray Dose (as applicable per Section 7.3.3)

7.3.4.1 Methods for Bounding Operational Period External Dose

NOTE: For individuals within the Isotopes Group working on the Y-12 campus, whose external 

dosimetry was provided by ORNL X-10, external dosimetry results are available in the form of 

primary documentation and summary reports for both photon and beta exposure for individual 

workers. These data are relevant to a portion of the class under evaluation from January 1, 1977 until 

the end of Isotopes Group operations on December 31, 1983 (See Section 5.1.3).
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Photon Dose

The primary method for reconstructing photon dose is the use of individual records. Badge-reading 

frequencies and thresholds of detection are known and documented. Methods are available for 

interpretation and adjustment of individual dosimetry data as needed (ORAUT-TKBS-0014-6; 

ORAUT-OTIB-0045; ORAUT-OTIB-0074).

Beta Dose

The primary method for reconstructing beta dose is the use of individual records. Methods are 

available for interpretation and adjustment of individual dosimetry data as needed (ORAUT-TKBS0014-6; ORAUT-OTIB-0046).

Neutron Dose

The primary method for reconstructing neutron dose is the use of individual records. Badge-reading 

frequencies and thresholds of detection are known and documented. Methods are available for 

interpretation and adjustment of individual dosimetry data as needed (ORAUT-TKBS-0014-6; 

ORAUT-OTIB-0045; ORAUT-OTIB-0051). 

Medical X-ray Dose

Occupational medical exposures to X-rays, when such screening X-rays are a condition of 

employment, are also included in EEOICPA dose reconstructions. During this time period, 

individuals at the Y-12 Site were required to have pre-employment, annual, and termination chest 

X-ray examinations. The Y-12 Occupational Medical Dose TBD (ORAUT-TKBS-0014-3) 

documents the method and feasibility of reconstructing these medical exposures.

7.3.4.2 Methods for Bounding Ambient Environmental External Doses

The bounding analysis uses the highest exposure reading from either the scan or the direct 

measurement presented in the scoping survey. This approach presented the most conservative method 

of estimating exposures and ensures that areas of high exposure levels within each grid were included 

in the site-wide average. An evaluation of the ambient external radiation exposures is discussed in 

Section 4.5.4 of ORAUT-TKBS-0014-4. The values provided in Table 4.4.4-1 of ORAUT-TKBS0014-4 are sufficiently bounding for occupational exposures and could be used for unmonitored 

workers. However, the availability of personnel monitoring data obviates the need for area 

monitoring data as a substitute (ORAUT-TKBS-0014-4).

7.3.5 External Dose Reconstruction Feasibility Conclusion

The data sources for photon, beta, and neutron doses, as well as occupational medical X-ray 

examinations and ambient environmental external doses, have been examined and found to be 

adequate for bounding EEOICPA external doses for monitored Y-12 workers for the entire period

under evaluation; this includes those working at the Isotopes Group facilities managed by ORNL X10 but located on the Y-12 campus.

The assessment of doses for unmonitored workers can be determined from the ambient environmental 

external dose methods defined in ORAUT-TKBS-0014-4. Based on NIOSH’s assessment of the 

available external data and the dose calculation methods available in ORAUT-TKBS-0014-4, NIOSH 
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concludes that it is feasible to bound external dose with sufficient accuracy for all monitored and 

unmonitored members of the evaluated class from January 1, 1977 through December 31, 1994. 

7.4 Evaluation of Petition Basis for SEC-00250

NIOSH did not find support for qualifying petition SEC-00250 for evaluation under any of the 

identified bases for work related to uranium. NIOSH did find support for qualifying petition 

SEC-00250 for evaluation under basis F.4., based on statements made in the SEC-00251 Y-12 

evaluation report related to thorium. The following subsections evaluate the assertions made on 

behalf of petition SEC-00250 for the Y-12 Plant. 

7.4.1 Uranium and Thorium Contamination Existed in the Machine Shop

Issue: The petitioner submitted Additional Supporting Document re contaminated machines 

(Contaminated Machines, 2012). 

Response: The cited document indicates that uranium and thorium contamination existed in the 

machine shop and that Y-12 workers handled thorium and uranium in the machining areas in 2012. 

While the source of the contamination detected in 2012 was not discussed in this document, it can be 

reasonably assumed to have been present throughout the period evaluated in this report (January 1, 

1977 through December 31, 1994). This report concludes that the reconstruction of internal dose from 

uranium is feasible during the entire evaluated period. Conclusions related to thorium are presented in 

this report for the period from January 1, 1977 through December 31, 1986. Evaluation of the period 

from 1987 through 1994 is currently reserved and will be addressed in the future. The justification of 

ending the evaluation period in December 31, 1994 is discussed in section 5.1.2. 

7.4.2 Petition Basis E.5. - Four Statements of Concern

Issue: The petitioner included statements in the petition regarding potential issues in support of the 

E.5 petition basis: The petition is based on one or more unmonitored, unrecorded, or inadequately 

monitored or recorded exposure incidents. The statements are: 

1. Y-12 Plant did not monitor for internal dose before 1980. 

2. Y-12 Plant incorrectly assumed that all uranium exposure involved soluble uranium when 

enriched uranium exposures involved insoluble uranium.

3. Workers exposed to uranium prior to the shutdown would not have routine fecal samples taken. 

4. The presence of fecal sample results in an individual’s monitoring records is a strong indicator 

that the worker was exposed to insoluble uranium compounds. This is incorrect.

Response: 

1. NIOSH has many claims-related documents that indicate Y-12 did monitor for internal exposure 

before 1980. Details are listed in the technical basis document for Y-12 (ORAUT-TKBS-14-5).

2. The Y-12 Uranium Exposure Study indicated that the insoluble uranium environment likely 

developed after the stand-down in 1994 and during the Y-12’s D&D phase (Eckerman, 1999). 
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During the EEIOCPA dose reconstruction process, all possible uranium solubility forms are 

considered, as stipulated in claimant dose-reconstruction reports. As shown in the excerpt below, 

which is typical, no internal dosimetry data were available; therefore, the dose from co-workers 

who were monitored was employed with all solubility types being assessed.

Internal dose monitoring records were not provided for the claimant. Since the claimant was 

not monitored for internal intakes during his employment at the Y-12 Plant, Y-12 coworker 

intakes were assigned based on the Technical Basis Document for the Y-12 National Security 

Complex Occupational Internal Dose. A review of the telephone interview indicated that the 

claimant worked at various areas throughout the Y-12 Plant where he performed duties as an 

[job title redacted] and [job title redacted]. Therefore, it is reasonable to apply coworker data 

for the claimant because no other information is available. Solubility Type F, Type M, and 

Type S uranium-234 were evaluated using the 95th percentile intake rates; the Type S uranium 

provided the highest doses and was used for the dose estimate. Associated radionuclides, 

including neptunium-237, plutonium-239, thorium-228, and technetium-99, were added in 

accordance with the Technical Basis Document for the Y-12 National Security Complex – 

Occupational Internal Dose. 

3. It is true that prior to the Y-12 stand-down (September 1994 through August 1998), routine fecal 

samples were not required. However, routine urinalysis and chest counts occurred throughout the 

period covered by this petition. Before the shutdown, fecal sampling was used on a non-routine 

basis and had been since the early 1960s. During the 1960s, fecal, urine, and in-vivo 

measurements were used jointly to investigate the clearance of less-soluble forms of uranium. 

Fecal sampling was discontinued several times but was reinstated in 1998 due to changes in 

workplace exposure conditions (ORAUT-0014-05, PDF p. 31).

4. The statement, “The presence of fecal sample results in an individual’s monitoring records is a 

strong indicator that the worker was exposed to insoluble uranium compounds,” is considered true 

in cases before and after the 1994-1998 stand-down. This statement was taken out of context from 

ORAUT-TKBS-0014-5, which states:

If a worker entered an area that was determined to contain Type S material, fecal and urine 

bioassays were implemented. If the worker entered an area that contained a more soluble 

form of uranium, urine bioassay only was used to estimate intakes. Thus, the presence of fecal 

sample results in an individual's monitoring records is a strong indicator that the worker was 

exposed to insoluble uranium compounds. (ORAUT-0014-05, PDF pp. 50-51) 

7.4.3 Petition Basis F.1. - One Statement of Concern

Issue: The petitioner included a statement from a cover letter from a former Y-12 worker (Redacted 

Name3, 2018) that was written to accompany the petition in support of the F.1 petition basis, 

Radiation exposures and radiation doses potentially incurred by members of the proposed class were 

not monitored either through personal monitoring or through area monitoring. The cover letter 

author states, “Y-12 did not monitor for internal dose prior to 1990.” The author then refers to the 

following footnotes from a Y-12 Plant Dosimetry Summary Report: 

(a) Monitoring not required, 
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(b) In accordance with regulations, internal dose and total dose were not calculated prior to 

1989.

Response:

This statement and referenced document indicate that the worker in question was not required to be 

internally monitored for specified periods of work at Y-12. The document does not describe 

monitoring performed for any other member of the petitioner-proposed class. 

7.4.4 Petition Basis F.2. - One Statement of Concern

Issue: The petitioner included a document in his petition, “Records Transmittal and Receipt Form, 

Document Accession Number Form,” to support the F.2 petition basis, Documents or statements 

provided by affidavit that indicate that radiation monitoring records for members of the proposed 

class have been lost, falsified, or destroyed; or that there is no information regarding monitoring, 

source, source term, or process from the site where the energy employees worked. 

To support this basis, the petitioner refers to the cited document, which expresses concerns with 

employment records, but does not refer to lost, falsified, or destroyed radiation monitoring records. 

The petitioner indicated that from the cited abstract for Y-12 Uranium Exposure Study: 

Following the recent restart of operations at the Y-12 Plant, the Radiological Control 

Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble 

rather than soluble uranium that presumably characterized most earlier Y -12 operations. These 

observations necessitated changes in the bioassay program, particularly the need for routine fecal 

sampling (Eckerman, 1999). 

Response:

During the NIOSH dose reconstruction process for internally-exposed workers, all solubility types are 

evaluated, and the most claimant-favorable result is used. Although fecal analysis can aid in the 

analysis of soluble uranium, routine urinalysis and other monitoring methods can also establish 

exposure to insoluble uranium (See E.5 basis discussion above). 

7.4.5 Petition Basis F.4. - One Document and Several Statements of Concern

Issue: The petitioner submitted a technical report to support basis F.4, A scientific or technical report, 

issued by a government agency of the Executive Branch of Government or the General Accounting 

Office, the Nuclear Regulatory Commission, or the Defense Nuclear Facilities Safety Board, or 

published in a peer-reviewed journal, that identifies dosimetry and related information that are 

unavailable (due to either a lack of monitoring or the destruction or loss of records) for estimating the 

radiation doses of energy employees covered by the petition 

To support this basis, the petitioner submitted a technical report, the Y-12 Uranium Exposure Study, to 

support basis F.4. The petitioner also submitted statements by email that indicate his desire to submit 

qualifying information that would allow NIOSH to expand the current SEC class for Y-12, which is 

discussed in the SEC-00251 petition evaluation report. The petitioner has discussed and commented 

on the contents of the SEC-00251 petition evaluation report and asked questions about submitting 

additional information relevant to thorium dose reconstruction. 
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Response:

The submitted technical report, Y-12 Uranium Exposure Study (Eckerman, 1999), was written in 

response to an observation that urinary and fecal bioassay data accumulated in the 1990s were not 

consistent with the guidance in use at Y-12, which was International Commission on Radiological 

Protection (ICRP) 54. This report is authored by Oak Ridge National Laboratory (ORNL), which is 

not a government agency of the Executive Branch of Government or the General Accounting Office, 

the Nuclear Regulatory Commission, or the Defense Nuclear Facilities Safety Board, or published in a 

peer-reviewed journal, as required for an F.4 basis. 

NIOSH does, however, consider the SEC-00251 evaluation report to be a scientific or technical report, 

issued by a government agency of the Executive Branch of Government, and therefore considers its 

own previous report for Y-12 as evidence as well.

In NIOSH’s previous evaluation of SEC-00251, it proposed an SEC class due to inability to bound 

potential thorium exposures for all employees at Y-12 for the period 1956-1976. This was due to the 

nature of the thorium in-vivo lung count results, which were reported in terms of milligrams (mg) of 

thorium in the lung. Without additional counter and calibration data for thorium decay products 

(Ac-228 and Pb-212), these results cannot be used to calculate bounding doses for internal thorium 

exposure (NIOSH, 2018). 

The SEC-00251 evaluation report indicated that isotopic-specific results (i.e., for Ac-228 and Pb-212) 

for thorium lung counts might be available starting in 1977. However, further evaluation of the data is 

required to verify this, as stated in SEC-00251: NIOSH has not ascertained the availability of these 

data at this time; therefore, it will continue to evaluate the feasibility of internal dose reconstruction 

for thorium at the Y-12 site beginning January 1, 1977 (NIOSH, 2018).

Since NIOSH was aware of the additional need to evaluate thorium dose-reconstruction feasibility for 

the period after 1976, and because the expansion of the SEC class was a stated desire of the petitioner, 

NIOSH accepted that this petition should qualify under basis F.4.

Beginning in September 1994, the plant was placed in a stand-down mode. This effectively stopped 

all routine work (and chronic exposure potential) in the process areas. Consequently, NIOSH used

this event to establish the end date of the class to be evaluated.
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7.5 Summary of Feasibility Findings for Petition SEC-00250

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

Plant from January 1, 1977 through December 31, 1994. NIOSH found that the available monitoring 

records, process descriptions, and source term data available are not sufficient to complete thorium 

internal dose reconstructions for the proposed class of employees from January 1, 1977 through July 

31, 1979. Thorium dose reconstruction feasibility after December 31, 1986 is reserved and will be 

evaluated in the future once data become available.

Table 7-3 summarizes the results of the feasibility findings at Y-12 Plant for each exposure source 

during the following periods: January 1, 1977 through July 31, 1979; August 1, 1979 through 

December 31, 1986; and January 1, 1987 through December 31, 1994. These feasibility findings also 

apply to those working at the Isotopes Group facilities managed by ORNL X-10 but located on the Y12 campus. 

Table 7-2: Summary of Feasibility Findings for SEC-00250

Source of Exposure

January 1, 1977 through 

July 31, 1979

Reconstruction Feasible 

(Yes or No)

August 1, 1979 through 

December 31, 1986

Reconstruction Feasible 

(Yes or No)

January 1, 1987 through 

December 31, 1994

Reconstruction Feasible 

(Yes or No)

Internal (U) Yes Yes Yes

Internal (Th) No Yes Reserved1 

Internal (calutron-cyclotronrelated radioisotopes) Yes Yes2 NA2

External (Gamma, Beta, Neutron) Yes Yes2 Yes

Occupational Medical X-ray Yes Yes Yes

1 NIOSH is currently working with the Y-12 site to receive post-1986 activity-based thorium progeny data (i.e., Ac-228 and 

Pb-212). Therefore, NIOSH is reserving its evaluation of internal exposure from thorium for the period from January 1, 

1987 through December 31, 1994 until activity-based thorium progeny data are available.

2 Isotopes Group calutron and cyclotron operations managed by ORNL X-10 but located on the Y-12 campus ended on 

December 31, 1983.

As of May 17, 2019, 3615 claims have been submitted to NIOSH for individuals who worked at Y-12 

Plant during the period under evaluation in this report. Dose reconstructions have been completed for 

3211 individuals (~89%). 

Although NIOSH found it 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 who worked at the Y-12 Plant from 

January 1, 1977 through July 31, 1979, but who do not qualify for inclusion in the SEC, may be 

performed using these data as appropriate. 
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8.0 Evaluation of Health Endangerment for Petition SEC-00250

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

governed by both EEOICPA and 42 C.F.R. § 83.13(c) (3). Under these requirements, if it is not 

feasible to estimate with sufficient accuracy radiation doses for members of the class, NIOSH must 

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

health of members of the class. Section 83.13 requires 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 employees 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 reviewed internal and external radiological monitoring data, various databases, technical 

basis documents, primary references, employee interviews, procedures, and activity reports to gain an 

understanding of the scope of the potential exposure scenarios during the period under evaluation. 

NIOSH’s evaluation found that some employees that worked during the period from January 1, 1977 

through July 31, 1979 may have accumulated chronic radiation exposures through intakes of thorium 

(and associated progeny). Consequently, NIOSH is specifying that health was endangered for those 

employees 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. NIOSH’s 

evaluation also determined that it is feasible to estimate the radiation dose for members of the NIOSHevaluated class from August 1, 1979 through December 31, 1986 with sufficient accuracy based on 

the sum of information from available resources. Therefore, a health endangerment determination is 

not required for that section of the evaluated period. 

9.0 Class Conclusion for Petition SEC-00250

Based on its full research of the class under evaluation, NIOSH has defined a single class of 

employees for which NIOSH cannot estimate radiation doses with sufficient accuracy. The NIOSHproposed class to be added to the SEC is: all employees of the Department of Energy, its predecessor 

agencies, and their contractors and subcontractors who worked at the Y-12 Plant in Oak Ridge, 

Tennessee, from January 1, 1977 through July 31, 1979.

Bounding dose calculations cannot be performed because the thorium lung-count data are not 

available in the appropriate form (i.e., activity units for Ac-228 and Pb-212). Thorium lung-count 

data in mass units are available; however, they cannot be used to estimate sufficiently accurate doses.

Bounding dose calculations can be performed from August 1, 1979 through December 31, 1986 

because thorium lung-count data are available in the appropriate form (i.e., activity units for Ac-228 

and Pb-212).
SEC-00250 07-17-19 Y-12 Plant

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NIOSH is currently working with the Y-12 site to receive post-1986 activity-based thorium progeny 

data (i.e., Ac-228 and Pb-212) that may allow NIOSH to estimate the maximum internal potential 

exposure from thorium to members of the evaluated class during the period from January 1, 1987 

through December 31, 1994. Therefore, NIOSH is reserving its evaluation of internal exposure from 

thorium for the period from January 1, 1987 through December 31, 1994 until activity-based thorium 

progeny data are available.

NIOSH has carefully reviewed all material sent in by the petitioner, including the specific assertions 

stated in the petition, and has responded herein (see Section 7.4). NIOSH has also reviewed available 

technical resources and many other references, including the SRDB, for information relevant to 

SEC-00250. In addition, NIOSH reviewed its NOCTS dose reconstruction database to identify 

EEOICPA-related dose reconstructions that might provide information relevant to the petition 

evaluation.

These actions are based on existing, approved NIOSH processes used in dose reconstruction for 

claims under EEOICPA. NIOSH’s guiding principle in conducting these dose reconstructions is to 

ensure that the assumptions used are fair, consistent, and well-grounded in the best available science. 

Simultaneously, uncertainties in the science and data must be handled to the advantage, rather than to 

the detriment, of the petitioners. When adequate personal dose monitoring information is not 

available, or is very limited, NIOSH may use the highest reasonably possible radiation dose, based on 

reliable science, documented experience, and relevant data to determine the feasibility of 

reconstructing the dose of an SEC petition class. NIOSH contends that it has complied with these 

standards of performance in determining the feasibility or infeasibility of reconstructing radiation dose 

for the class under evaluation.
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SEC-00250 07-17-19 Y-12 Plant 

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10.0 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 

Ashley, 1995, A Technical Study of TLD Beta Calibration Factor for Exposure to Depleted Uranium, 

Y/DQ-59, J. C. Ashley, J. E. Turner, M. L. Souleyrette, R. S. Bogard, and K. L. McMahan; Y-12 

Plant, Oak Ridge, Tennessee; June 1995; SRDB Ref ID: 16474 

Batte, 1983, Data Reduction Software for an In-Vivo Radiation Monitoring System; Z. Batte; June 

1983; SRDB Ref ID: 174170 

CCCC, 1951, Progress Report - Part I, Electromagnetic Research Division, July 1, 1951 to September 

31, 1951, ORNL-1173, Carbide and Carbon Chemicals Company, Oak Ridge National Laboratory; 

SRDB Ref ID: 11943 

Cofield, 1960, Radioactivity of Thorium and Feasibility of In-Vivo Counting, Y-1280, R. E. Cofield, 

Union Carbide Nuclear Company; issued January 5, 1960; SRDB Ref ID: 112573 

Cofield, 1961, Radioactivity Distribution in the Metallurgical Processing of Thorium, R. E. Cofield, 

Union Carbide Nuclear Company; May 30, 1961; SRDB Ref ID: 165972 

Contaminated Machines, 2012, Additional Supporting Document from Petitioner re Contaminated 

Machines, no date, no author; content mentions 2012; SRDB Ref ID: 176786

DCAS-PR-004, Internal Procedures for the Evaluation of Special Exposure Cohort Petitions, Rev. 1; 

National Institute for Occupational Safety and Health (NIOSH); Cincinnati, Ohio; April 15, 2011; 

SRDB Ref ID: 94768 

Delta View Data, 1989–1995, Y-12 Whole-Body Count Data, Y-12 Plant, data for various dates from 

1989 through 1995; SRDB Ref ID: 176611 

Detail File Layout, undated, ORGDP Y-12 WBC Detail File Layout, Y-12 Plant; no identified author 

or date; SRDB Ref ID: 176594 
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Eckerman, 1999, Y-12 Uranium Exposure Study, ORNL/TM-1999/114, K. F. Eckerman and G. D. 

Kerr, Lockheed Martin Energy Systems, Oak Ridge National Laboratory, Oak Ridge, Tennessee; 

August 5, 1999; SRDB Ref ID: 11600 

Henderson, 1991, Evaluation of Radiation Exposure in Metal Preparation Depleted Uranium Process 

Areas, Y/DQ--5/R1, Henderson, M. D., Martin Marietta Energy Systems, Y-12 Plant, Oak Ridge, 

Tennessee, May 1991; SRDB Ref ID: 8538 

Hibbs, 1960, Thorium Fabrication, R. F. Hibbs, J. M. Case and W. K. Whitson; Union Carbide 

Nuclear Company; February 25, 1960; SRDB Ref ID: 166620 

Hibbs, 1961, Thorium Program at Y-12, R. F. Hibbs; Union Carbide Nuclear Company; October 4, 

1961; SRDB Ref ID: 23619 

Hunt, 1992, Y-12 Plant Health Physics Quarterly Report for October through December 1992; 

compiled by J. B. Hunt; October through December 1992; SRDB Ref ID: 152447, PDF p. 10 

Kerr, 1992, A Brief History of the Health and Safety Research Division at Oak Ridge National 

Laboratory, ORNL/M-2108, G. D. Kerr, R. H. Ritchie, S. V. Kaye, and J. S. Wassom; Martin 

Marietta Energy Systems, Oak Ridge National Laboratory; July 1992; SRDB Ref ID: 42109 

Kerr, 2004, Historical Evaluation of the Film Badge Dosimetry Program at the Y-12 Facility in Oak 

Ridge, Tennessee: Part 2 – Neutron Radiation, Rev. 00, G. D. Kerr, et al, Ker Consulting Company, 

Oak Ridge Associated Universities, 2004; SRDB Ref ID: 16843 

Livingston, 1952, The Oak Ridge 86-Inch Cyclotron, ORNL-1196, R. S. Livingston and A. L. Boch, 

Oak Ridge National Laboratory, Carbide and Carbon Chemicals Company, Oak Ridge, Tennessee;

June 12, 1952; SRDB Ref ID: 11942 

Lung Count Spreadsheet, 1984–1995, Y-12 Lung Count Spreadsheet; data for various dates from 1984 

through 1995; SRDB Ref ID: 176724 

McLendon, 1963, Y-12 Radiation Safety Manual, Y-KB-29, J. D. McLendon, Union Carbide 

Corporation, Oak Ridge, Tennessee; October 31, 1963; SRDB Ref ID: 8541 

McRee, 1965, Y-12 Radiation Safety Manual, Y-1401–Revised, P. C. McRee, C. M. West, and J. D. 

McLendon, editors, Union Carbide Corporation, Nuclear Division, Oak Ridge, Tennessee; May 11, 

1965; SRDB Ref ID: 8577 

NaK Accident, 2000, Multiple Injury Accident Resulting from the Sodium-Potassium Explosion in 

Building 9201-5 at the Y-12 Plant, U.S. Department of Energy, Office of Oversight, Office of 

Environment, Safety and Health; February 2000; SRDB Ref ID: 79164 

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

for Occupational Safety and Health (NIOSH); June 13, 2005; SRDB Ref ID: 100832 

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

National Institute for Occupational Safety and Health (NIOSH); April 7, 2006; SRDB Ref ID: 100833 
SEC-00250 07-17-19 Y-12 Plant 

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NIOSH, 2007, External Dose Reconstruction Implementation Guidelines, OCAS-IG-001, Rev. 03, 

National Institute for Occupational Safety and Health (NIOSH) Office of Compensation Analysis and 

Support (OCAS), Cincinnati, Ohio, November 21; SRDB Ref ID: 38864 

NIOSH, 2008, SEC Petition Evaluation Report for Petition SEC-00098, Y-12 Plant; National Institute 

for Occupational Safety and Health (NIOSH); May 14, 2008; SRDB Ref ID: 100834 

NIOSH, 2011, SEC Petition Evaluation Report for Petition SEC-00186, Y-12 Plant; National Institute 

for Occupational Safety and Health (NIOSH); April 22, 2011; SRDB Ref ID: 100831 

NIOSH, 2018, SEC Petition Evaluation Report for Petition SEC-00251, Y-12 Plant; National Institute 

for Occupational Safety and Health (NIOSH); November 27, 2018; SRDB Ref ID: 176735 

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 

Oliver, 2003, Truhistory, Personal Correspondence (email), R. W.Oliver, August 28, 2003; SRDB Ref 

ID: 8519 

Oliver, 2007, Y-12 Questions, Personal Correspondence (email), R. W. Oliver, September 4, 2007; 

SRDB Ref ID: 35889 

ORAUT-OTIB-0006, Dose Reconstruction from Occupationally Related Diagnostic X-Ray 

Procedures, Rev. 04, Oak Ridge Associated Universities; effective June 20, 2011; SRDB Ref ID: 

98147

ORAUT-OTIB-0021, External Coworker Dosimetry Data for the X-10 Site, Rev. 01, Oak Ridge 

Associated Universities; effective November 7, 2006; SRDB Ref ID: 29957

ORAUT-OTIB-0044, Historical Evaluation of the Film Badge Dosimetry Program at the Y-12 

Facility in Oak Ridge, Tennessee: Part 1 – Gamma Radiation, Rev. 01, Oak Ridge Associated 

Universities; effective April 29, 2013; SRDB Ref ID: 124944

ORAUT-OTIB-0045, Historical Evaluation of the Film Badge Dosimetry Program at the Y-12 Plant 

in Oak Ridge, Tennessee: Part 2 – Neutron Radiation, Rev. 01, Oak Ridge Associated Universities; 

effective November 30, 2009; SRDB Ref ID: 77243

ORAUT-OTIB-0046, Historical Evaluation in the Film Badge Dosimetry Program at the Y-12 Plant 

in Oak Ridge, Tennessee: Part 3 – Beta Radiation, Rev. 00, Oak Ridge Associated Universities; 

effective June 22, 2007; SRDB Ref ID: 32523

ORAUT-OTIB-0051, Effect of Threshold Energy & Angular Response of NTA Film on Missed 

Neutron Dose at Oak Ridge Y-12, Rev. 00; Oak Ridge Associated Universities; effective May 15, 

2006; SRDB Ref ID: 29977
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ORAUT-OTIB-0064, Coworker External Dosimetry Data for the Y-12 National Security Complex, 

Rev. 02, Oak Ridge Associated Universities; April 29, 2013; SRDB Ref ID: 124947

ORAUT-OTIB-0074, Potential Missed Dose to Nuclear Weapons Assemblers at the Y-12 Plant 

During the Period from 1958 to 1990, Rev. 00; Oak Ridge Associated Universities; effective March 

13, 2009; SRDB Ref ID: 62716

ORAUT-OTIB-0075, Use of Claimant Datasets for Coworker Modeling, Rev. 01; Oak Ridge 

Associated Universities; effective June 17, 2016; SRDB Ref ID: 157060

ORAUT-OTIB-0076, Guiding Reconstruction of Intakes of Thorium Resulting from Nuclear Weapons 

Programs, Rev. 00, Oak Ridge Associated Universities; July 10, 2014; SRDB Ref ID: 133669

ORAUT-OTIB-0079, Guidance on Assigning Occupational X-Ray Dose Under EEOICPA for X-Rays 

Administered Off Site, Rev. 01; Oak Ridge Associated Universities; effective March 18, 2016; SRDB 

Ref ID: 152173

ORAUT-RPRT-0090, Rev. 00, Neutron Dose from Highly Enriched Uranium, Oak Ridge Associated 

Universities; effective March 29, 2018; SRDB Ref ID: 170258 

ORAUT-TKBS-0014-1, Y-12 National Security Complex Introduction, Rev. 01, Oak Ridge 

Associated Universities; October 24, 2006; SRDB Ref ID: 30036 

ORAUT-TKBS-0014-2, Y-12 National Security Complex – Site Description, Rev. 02, Oak Ridge 

Associated Universities; November 8, 2007; SRDB Ref ID: 36045 

ORAUT-TKBS-0014-3, Y-12 National Security Complex – Occupational Medical Dose, Rev. 01, Oak 

Ridge Associated Universities; June 18, 2007; SRDB Ref ID: 32461 

ORAUT-TKBS-0014-4, Y-12 National Security Complex – Occupational Environmental Dose, Rev. 

01, Oak Ridge Associated Universities; July 20, 2006; SRDB Ref ID: 30042 

ORAUT-TKBS-0014-5, Y-12 National Security Complex – Occupational Internal Dose, Rev. 03, Oak 

Ridge Associated Universities; March 12, 2012; SRDB Ref ID: 109202 

ORAUT-TKBS-0014-6, Y-12 National Security Complex – Occupational External Dosimetry, Rev. 

02, Oak Ridge Associated Universities; December 18, 2009; SRDB Ref ID: 77701 

ORNL, 1995, Work Plan for the Isotopes Facilities Deactivation Project at Oak Ridge National 

Laboratory, Oak Ridge, Tennessee; Isotopes Facilities Deactivation Project of Oak Ridge National 

Laboratory (ORNL); Issued August 1995; SRDB Ref ID: 124128 

Pepper, 2000, The Health Effects of Downsizing in the Nuclear Industry: Y-12 Plant, Oak Ridge 

Reservation, L. D. Pepper, Boston University School of Public Health; August 2000; SRDB Ref ID: 

79533 
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Personal Communication, 2012, Personal Communication with Former Oak Ridge National 

Laboratory Employee; telephone interview by ORAU Team and NIOSH; March 15, 2012, SRDB Ref. 

ID 110639

Personal Communication, 2018a, Personal Communication with Former Y-12 Plant Employee; 

in-person interview by ORAU Team; August 15, 2018; SRDB Ref ID: 173936

Personal Communication, 2018b, Personal Communication with Former Y-12 Plant Employee; 

in-person interview by ORAU Team; August 16, 2018; SRDB Ref ID: 173937

Personal Communication, 2018c, Personal Communication with Former Y-12 Plant Employee; 

in-person interview by ORAU Team; August 16, 2018; SRDB Ref ID: 173938

Personal Communication, 2018d, Personal Communication with Former Y-12 Plant Employee; 

in-person interview by ORAU Team; August 16, 2018; SRDB Ref ID: 173939

Personal Communication, 2018e, Personal Communication with Former Y-12 Plant Employee; 

in-person interview by ORAU Team; August 16, 2018; SRDB Ref ID: 174343

RCO/TR-013, 2001, Atypical Radionuclide Assessment at the Y-12 National Security Complex, Y-12 

National Security Complex, Radiological Control Organization, Environment, Safety and Health; May 

17 2001; SRDB Ref ID: 12492 

Redacted Name1, 2012, Documented Communication regarding Thorium Operations, telephone 

interview with ORAU Team; February 15, 2012; SRDB Ref ID: 109819 

Redacted Name2, 2012, Documented Communication regarding Thorium Operations, telephone 

interview with ORAU Team; February 23, 2012; SRDB Ref ID: 109522 

Redacted Name3, 2018, Special Exposure Cohort Petition for Y-12 Plant, correspondence to 

NIOSH DCAS; [Name redacted]; October 18, 2018; SRDB Ref ID: 176784 

Souleyrette, 2003, Summary of Historical Monitoring Techniques Provided to NIOSH for EEOICPA 

Data Requests, M. L. Souleyrette, BWXT Y-12, Y-12 National Security Complex, Oak Ridge, 

Tennessee, February 18, 2003; SRDB Ref ID: 8586 

Thorium Air Samples, 1960-76, Excel Spreadsheet Containing Air Sample Results for Y-12 

for 1960-1976, Y-12 Plant, Oak Ridge National Laboratory, Union Carbide Corporation, 

Nuclear Division; various dates in 1960-1976; SRDB Ref ID: 141457 

Thorium Flow Chart, 1963, Thorium Process Flow Chart, Union Carbide Nuclear Company; 1963; 

SRDB Ref ID: 166621 

Thorium Lung Counts, 2005, Thorium Lung Count Results by Year (1958-1982), BWXT Y-12, Excel 

sheets containing Y-12 thorium lung count results; provided to NIOSH on May 13, 2005; SRDB Ref 

ID: 17073 

Thorium Machining, 1960, Thorium Machining, Building 9766; Union Carbide Nuclear Company; 

January 19, 1960; SRDB Ref ID: 166623 
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Thorium Melt, 1969, Old Thorium Melt Operation, internal correspondence to E. H. Johnson from M. 

Sanders, Union Carbide Corporation, Nuclear Division; June 17, 1969; SRDB Ref ID: 166264, PDF 

pp. 5-6 

Watkins, 1993, Data Collection, Validation and Description for the Oak Ridge Nuclear Facilities 

Mortality Study, 1993; J. P. Watkins, J. L. Reagan, D. L. Cragle, E. L. Frome, C. M. West, D. J. 

Crawford-Brown, and W. G. Tankersley; title identifies 1993; SRDB Ref ID: 79353 

West, 1961a, An Evaluation of the Health Physics Problems from Thorium and Its Daughters in a 

Thorium Purification and Fabrication Process, C. M. West, Union Carbide Nuclear Company April 

28, 1961; SRDB Ref ID: 166611 

West, 1961b, Rule of Thumb for Computing Thorium Body Burden from In-Vivo Counts, internal 

correspondence to C. M. West from L. M. Scott, Union Carbide Nuclear Company; November 21, 

1961; SRDB Ref ID: 32615 

West, 1965, Health Physics Considerations Associated with Thorium Processing, Y-KB-53, C. M. 

West, Union Carbide Corporation, Nuclear Division; January 19, 1965; SRDB Ref ID: 11596 

West, 1977, Thorium (Natural) and Its Compounds, C. M. West and L. M. Scott; Union Carbide 

Corporation, Nuclear Division; March 1977; SRDB Ref ID: 166612 

West, 1993, Brief History of the Y-12 External Monitoring Program, H. West, internal memorandum 

to D. Cragle, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee; June 7. 1993; 

SRDB Ref ID: 8532 

Wilcox, 2001, An Overview of the History of Y-12, 1942 - 1992, A Chronology of Some Noteworthy 

Events and Memoirs, W. J. Wilcox, American Museum of Science and Energy, Oak Ridge, 

Tennessee, August 2001; SRDB Ref ID: 9609 
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Attachment One: Data Capture Synopsis

Table A1-1: Summary of Holdings in the SRDB for the Y-12 Plant

Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Primary Site/Company Name: Y-12 Plant

1942-present, DOE 

Alternate Site Names: Y-12 National Security Complex

Physical Size of the Site: 811 acres holding over 350 

buildings.

Site Population: 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. In October 2018, Y-12 reported more than 4,700 

federal and contractor employees work at the site.

Awaiting release of a Documented Communication from DOE 

Headquarters, whole body count records, and an external dosimetry 

flat file.

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, dosimetry quality control program information, 

building radiation and contamination periodic surveys, neutron-photon 

radiation surveys, container surveys for outgoing shipments, 

calibration and operation of the in-vivo lung counter, individual 

employee bioassay and film/TLD reports, plant health physics 

quarterly reports, thorium contamination survey results, thorium air 

sample results, air sampling system and locations, thorium fabrication, 

thorium machining, thorium processing, a process knowledge expert 

interview, data reduction software for in-vivo counting, dosimetry data 

with thorium in-vivo counts for a Y-12 employee, a 1964 Y-12 

radiation safety manual, a whole body count column header key, and 

1989-1995 whole body count data.

OPEN 804

State Contacted: NA State was not contacted due to Y-12 being an active Department of 

Energy site.

NA NA
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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Albany Research Center A 1950 report on the chemical properties of californium. 03/21/2013 2

Ames Laboratory Ames histories, 1951-1953 radiation work permits, survey reports, and 

thorium shipments to other facilities.

01/25/2016 8

Argonne National Laboratory-East Organization of National Nucleonic Program, personnel procedure for 

transferring to Y-12 in 1943, and plutonium scrap processing 

information.

04/02/2008 4

Battelle Laboratory-King Avenue Thorium reports, a 1951 material balance report, and a nuclear battery 

report.

04/14/2011 5

Brookhaven National Laboratory Ambient air monitoring parameters at DOE facilities and monthly 

reports.

10/22/2008 4

Cincinnati Public Library A Manhattan Project History. 08/06/2008 1

Cincinnati Operations Center Library Y-12 photographs and map key, urinalysis reports, an ORNL visitor 

guide, modifications to the ORNL Health Center, external exposure 

summaries 1989-1991, a DOELAP status report for the Centralized 

External Dosimetry System, a 1994 internal dosimetry review, the 

1990 survey and characterization of Building 9201-2, a DOELAP 

reaccreditation application, the technical basis for augmenting the 

criticality alarm system, the air monitoring technical basis document, 

the DOE Office of Oversight Radiological Task Team reports, the 

survey and release protocol for wooden items, the implementing order 

for 10 CFR 835, and a survey and release plan for heavy equipment.

07/16/2018 16

Claimant Provided Work products from inter-agency working groups and links between 

exposure to occupational hazards and illnesses in the DOE contractor 

workforce, an extrusion video, radon measurements, a site walking 

tour, a contamination survey and environmental report, a hearing 

before the workers' compensation board state of New York, and a Y12 building directory.

05/10/2018 7

Colorado Mesa University Recovery of uranium from carnotite ores, progress reports of carnotite 

studies, separation of uranium from urine, stack sampling, radiation 

emergencies, and new methods for interpreting neutron data from 

various dosimeter types.

10/16/2012 10

Curtiss-Wright Shipping information and orders. 04/24/2009 1
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Department of Labor / Paragon Background report and evaluation of resurvey requirements for the 

former Atomic Energy Commission portion of the Lake Ontario 

Ordinance Works (LOOW), request for scrap evaluation, shipment of 

Schenectady wastes to Oak Ridge, a complex-wide mixed waste 

report, a mercury waste management report, and a visit from Cotter 

Corporation personnel.

10/29/2014 12

DOE Albuquerque Complex NNSA NURE activation analysis system correspondence. 01/13/2012 1

DOE Environmental Consolidated Business Center 

(EMCBC) - Denver

Rocky Flats thorium shipments to Y-12. 02/12/2014 1

DOE Environmental Information Center Y-12's receipt of gold from the Paducah metals recovery program. 07/20/2011 1

DOE Environmental Measurements Laboratory Air sampling for the control of internal exposure from enriched 

uranium at Y-12, a beryllium study, criticality alarms and accident 

dosimetry, and in-vivo counting as a device for evaluating uranium 

exposure.

01/21/2011 4

DOE Germantown Beryllium history, waste disposal, monthly accountability reports, 

thorium information, site histories, Manhattan District History 

sections, records holding area search procedures, DOE reasonable 

search protocol spreadsheet, and a data tracking spreadsheet.

09/17/2015 19

DOE 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, budget reviews, an accidental 

radiation excursion at Y-12, a contractor list, and history of Hanford.

08/30/2011 51
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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

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, thorium bioassay, recycled 

uranium data, trip reports, FUSRAP reports, environmental reports, 

uranium urine exchange program information, report of analysis, and 

TLD monitoring.

04/07/2016 164

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.

02/01/2012 83

DOE Legacy Management - MoundView (Fernald 

Holdings, includes Fernald Legal Database) / Albany 

Research Center

The 1958 symposium on uranium industry occupational health 

experiences.

09/30/2003 1

DOE Legacy Management - Westminster Complex-wide external dosimetry technical basis document, 

plutonium/actinide recovery history, lifetime dose calculations from 

systemic burden and lung count data, technical services quarterly 

report, Elza Gate bioassays sampling logs, and reports of analysis.

01/14/2016 5

DOE Nuclear Materials Management and Safeguards 

System (NMMSS)

Material transfers between Y-12 and Rocky Flats. 07/10/2013 2
SEC-00250 07-17-19 Y-12 Plant

65 of 81

Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

DOE Oak Ridge Operations Material accountability reports, description of thorium processing, 

safety meetings, PCB meetings, bioassay results, external exposure 

results, TLD processing, fluorine control, artificial urine reports, 

asbestos worker files, the mobile body counter, U-233 history and 

inventories, trip reports, TLD problems, respiratory program 

occurrence report, periodic progress reports, and environmental 

reports. 

01/13/2014 64

DOE Oak Ridge Operations Records Holding 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, monthly production reports, production statistics 

and thorium inventories, 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.

08/14/2015 162

DOE Office of Scientific and Technical Information 

(OSTI)

Closed-cycle beta process, alpha II calutron development, uranium 

recovery by spray cleaning, thorium receipts, radiological surveys, 

pocket meter logbook notes, material transfers, coating of metallic 

thorium, material inventories, health physics logbooks, personnel 

monitoring, internal exposure study, applied health physics program 

review, calibrating and reading TLDs, periodic reports, and airborne 

uranium.

09/24/2018 85

East Tennessee Technology Park (ETTP) & Oak Ridge 

Gaseous Diffusion Plant (K-25)

Special form material procedures, health physics procedures, 

implementation plan for DOE Order 5480.11, the ETTP internal 

dosimetry program, technical basis, and evaluations, 10 CFR 835 

implementing program documents, worker safety and health program 

documents, a nondestructive assay survey, 1958 radiation protection 

training programs, and Oak Ridge Reservation annual air emission 

reports. 

01/11/2017 43

Federal Records Center - Atlanta Uranium tolerances, finger film, biological research at Mound, tritium

information, and an Oak Ridge Operations Office health protection 

status report.

08/12/2004 5

Federal Records Center - Boston Personnel termination exposure summaries. 04/27/2012 1
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Federal Records Center - Chicago Contamination control limits, a tritium release limits position paper, 

radiological control manuals, and technical basis documentation.

06/20/2013 6

Federal 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, a Health Physics Division annual report, 

transfers of highly enriched uranium, a RCRA facility investigation, 

and dose estimates for a Y-12 incident.

06/02/2014 7

Federal Records Center - Denver Mortality among radiation workers at a plutonium weapons facility, 

beryllium purchasing, fire protection workshop proceedings, a 1967 

review of criticality accidents, and a listing of mixed waste streams.

01/25/2012 5

Federal Records Center - Kansas City Reports of urinalysis with sample routing logs, Tiger Team findings, 

and the process for handling contaminated parts returned to Kansas 

City Plant.

10/09/2013 3

Federal Records Center - Kansas City, Bannister 1990-1991 bioassay sample results and 1990 occupational exposure 

report summaries.

07/16/2008 2

Federal Records Center - Lee's Summit DOE unusual incident reports, a volumetric release analysis, 

environment, safety, and health performance indicators, 1988 bioassay 

results, a West Valley fact book, analyses of Tiger Team findings, 

waste minimization, mixed waste evaluation and strategies, and an 

effluent system report.

05/19/2016 34

Federal Records Center - San Bruno Beta run reports, personnel medical records handling, personnel 

assignment logs, schedule for track B, a personnel dosimetry 

intercomparison, medical and health physics quarterly reports, 

plutonium and fission products metabolism, and health chemistry 

accident reports.

02/12/2018 14

Fernald / SC&A Mobile in-vivo radiation monitoring laboratory brochure. 06/26/2003 1

General Atomics The 1958 criticality incident at Y-12. 08/16/2005 1

Goldberg, Persky, and White PC - Mancuso Collection A 1973 contractor list, a records retention discussion, correspondence, 

and a local news article regarding a small fire in 1976.

01/10/2017 8

Hagley Museum & Library General history of Clinton Engineer Works, race for the bomb, the 

Hanford story, and uranium experimental program on heat treatment.

09/29/2010 8
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Hanford In-vivo counting method for determining the uranium lung burden, 

annual and monthly progress reports, environmental monitoring and 

protection committee information, smelting uranium-contaminated 

ferrous metal scrap, production of tritium, health physicist reports, a 

waste water treatment review, inventories, material losses, uranium 

mass balance project document index and attachments, accountability 

reports, accountability survey data, and inspection criteria for enriched 

uranium powder.

04/16/2019 43

Idaho National Laboratory (INL) Material transfers between Y-12 and INL facilities, handling of Y-12 

material at INL, correspondence, visitor badge reports, criticality 

safety evaluations, a documented communication, a list of 

publications, visitor traffic logs, a contaminated rail car report, and 

employee previous exposure histories.

08/29/2018 52

INL Electronic Document Management System (EDMS) The results of an EDMS keyword search. 06/29/2016 1

Interlibrary Loan Environmental levels of radioactivity at Atomic Energy Commission 

installations, work history reports for oxide conversion facility, 

proceedings of a short criticality safety course, the Seaborg journal, 

and the proceedings of an incineration conference.

05/29/2012 24

Internet - Defense Technical Information Center (DTIC) An occupational dose reconstruction bibliography, uranium alloy 

metallurgy bibliography, defense nuclear facilities safety board reports 

to Congress, actinide research quarterly reports, physical metallurgy of 

uranium alloys, the characterization of enriched uranium oxide 

particles, best manufacturing practices, Y-12 nuclear forensic 

capabilities and experience, and the Defense Nuclear Facilities Safety 

Board 23rd annual report to Congress.

03/26/2019 24

Internet - DOE Comprehensive Epidemiologic Data 

Resource (CER)

Health physics hygiene progress report and the impact of downsizing 

and reorganization on employee health and well-being at the DOE Y12 Plant.

01/23/2010 3

Internet - DOE Hanford Declassified Document Retrieval 

System (DDRS)

Fourth Atomic Energy Commission Air Cleaning Conference, 

specifications for Savannah River Site slugs, periodic department 

reports, a trip report, and a shipment of uranium rods to Y-12. 

09/22/2015 7

Internet - DOE Health, Safety, and Security (HSS) 10 CFR 835 exemption requests. 02/07/2017 2

Internet - DOE Legacy Management Preliminary survey of the Elza Gate warehouse area, removal of 

uranium from soil, beryllium-associated worker registries, annual 

occupational exposure reports, a former worker medical screening 

report, and documentation supporting the over packing of waste 

thorium at Fernald including Y-12 generated waste.

04/08/2019 11
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Internet - DOE Legacy Management Considered Sites A 1951 monthly progress report and a mixed waste inventory report. 04/24/2012 2

Internet - DOE National Nuclear Security Administration 

(NNSA) Library

Violation citations related to a uranium fire, the final site-wide 

environmental impact statement, the history of the Nuclear Materials 

Management and Safeguards System, and the consolidation of the 

site's nuclear footprint.

11/16/2015 5

Internet - DOE Noncompliance Tracking System (NTS) Noncompliance with Nevada Test Site waste acceptance criteria, a 

discussion of isolated non-uranium contamination areas, inadequate 

control of materials used in maintenance of enriched uranium oxide, 

calibration program deficiencies, a glovebox fire, deficiencies in 

radiological work permit compliance, missed routine bioassay 

samples, and unanalyzed material in Building 9720.

03/11/2019 9

Internet - DOE Oak Ridge Operations Release of a parcel of land to the city of Oak Ridge, the demolition of 

Building 3704, photographs of Building 9401-2, and the 2016 Oak 

Ridge Reservation annual environmental report.

05/01/2018 4

Internet - DOE Occurrence Processing and Reporting 

System (ORPS)

Personnel contamination reports and roll-ups, legacy contamination 

discoveries, contaminated items discovered areas controlled for 

contamination, personnel intakes of radioactive material, radioactive 

material spills, uranium fires, and criticality safety infractions.

05/03/2019 51

Internet - DOE Office of Scientific and Technical 

Information (OSTI)

The 2006 Oak Ridge Reservation annual environmental report, a 1958 

Argonne National Laboratory Chemical Engineering Division report, a 

2016 air emissions report, and a scoping package for environmental 

remediation.

04/02/2019 4

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, 

uranium dust exposure and lung cancer risk in four uranium processing 

operations, trip reports, Oak Ridge Institute of Nuclear Studies 

medical research reports, a californium-252 report, fuel slug studies, 

Manhattan Project field progress reports, material transfers, a plant 

tour, National Radiobiology Project interviews, Massachusetts General 

Hospital uranium study, calculation of potential incident doses, 

radiobiology reports, neutron exposure dosimetry by in-vivo sodium24 measurements, organization charts, material transfer security 

requirements, and an injury claim.

09/06/2018 149
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

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, a Pinellas Plant 

feasibility study, a mathematical model for lung counting, the 

feasibility of in-vivo thorium measurements, ORNL Chemical 

Technology Division reports, a 2011 DOE occupational radiation 

exposure report, a nuclear accident dosimetry intercomparison study, 

and the abstracts from a pollution prevention conference. 

08/28/2013 47

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, Y-12 Plant solid waste 

management system, a beryllium exposure assessment, a uranium 

hydride report, and hazardous and mixed waste generation.

08/26/2013 170
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SRDB

Internet - DOE OSTI SciTech Connect High-level radioactive waste reports, low-level radioactive waste 

reports, spent nuclear fuel strategic plans, spent fuel storage, 

environmental reports, groundwater protection and quality reports, 

waste generation and pollution prevention reports, a tank 

characterization survey, a Y-12 Tiger Team assessment, dosimetry 

quality assurance, the status of environmental initiatives, periodic 

project reports, life cycle analysis approach to D&D projects, strategic 

special nuclear material inventory differences, an Oak Ridge dose 

reconstruction report, and control technology for radioactive 

atmospheric emissions.

08/28/2018 107

Internet - Energy Employees Claimant Assistance Project 

(EECAP)

A RCRA landfill analysis for the United Nuclear Corporation disposal 

site, assessment of enriched uranium storage safety issues, 

Development Division periodic reports, operation of the chip oxidation 

facility, uranium removal from contaminated soils, and reduction of 

airborne radioactivity levels at the Building 9201-5 arc melt sawing 

operation.

03/26/2014 13

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, Y-12 history and fact sheet, 

environmental restoration, DOE occupational radiation exposure 

reports, characterization of contaminated scrap metal, oral history 

interviews, transuranic waste management, the characterization 

strategy for Building 9201-5, contractor performance evaluation 

reports, the determination of thorium in thorium metal, and a Y-12 fact 

sheet. 

09/13/2018 508
SEC-00250 07-17-19 Y-12 Plant

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SRDB

Internet - Hathitrust A 1962 dosimetry badge orientation experiment. 10/21/2015 1

Internet - Health Physics Journal Identification of Oak Ridge Reservation emission sources, a urinalysis 

intercomparison study, an analysis of cesium body burdens, the 

retention of uranium in the chest, radioactivity distributions in the 

metallurgical processing of thorium, and a comparison of lung dose 

estimates from air sampling and bioassay data.

03/26/2019 7

Internet - Idaho National Laboratory (INL) Shipments of purified uranium powder to Oak Ridge. 07/13/2016 3

Internet - International Atomic Energy Agency (IAEA) The status of stable isotope enrichment and services. 12/19/2016 1

Internet - Journal of Occupational and Environmental 

Hygiene

No relevant documents identified. 03/26/2019 0

Internet - National Academies Press Complex-wide safety and health management, research opportunities 

in D&D projects, Dr. Frank Spedding biographical memoirs, and 

radioactive waste reports.

03/17/2015 5

Internet - National Environmental Publications Information 

System (NEPIS, US EPA)

Environmental radiation data, environmental cleanup standards and 

regulations, transuranium elements dose limits and radiation 

protection, Y-12 records of decision, and an overview of waste 

solidification and stabilization at Superfund sites. 

02/09/2016 15

Internet - National Institute for Occupational Safety and 

Health (NIOSH)

Special exposure cohort petition evaluation reports, NIOSH residual 

radioactive and beryllium contamination reports, designation of 

additional members of the SEC, the minutes of Work Group meetings, 

the Kansas City Plant issues matrix, and an Advisory Board on 

Radiation and Worker Health review of the Y-12 site profile.

11/01/2018 30

Internet - National Technical Information Service (NTIS) Feasibility study of the correlation of lifetime health and mortality 

experience of AEC and AEC contractor employees’ progress reports.

08/21/2006 2

Internet - Nuclear Regulatory Commission (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 

database U.S. spent fuel and radioactive waste inventories, projections, 

and characteristics, a soil management plan for the Oak Ridge Y-12, 

disposition of surplus highly enriched uranium, environmental impact 

statements, a Y-12 safety analysis report, advance notifications of 

shipments, facility hazard assessments, export licenses and shipments, 

NRC export license applications, and a 60-day notification of a 

materials transfer incident. 

09/28/2017 131
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SRDB

Internet - Oak Ridge National Laboratory (ORNL) ORNL Division and Laboratory periodic reports mentioning Y-12, 

radiation safety for Y-12 Building 9204-3 isotope separation 

operations, report on a calutron ion source, the recovery of uranium 

from acid liquors, a 1979 thorium utilization progress report, and Oak 

Ridge Reservation annual environmental reports. 

09/26/2017 164

Internet - University of North Texas The evaluation of Organic Moderated Reactor Experiment fuel 

elements containing uranium oxide from Oak Ridge.

09/18/2018 1

Internet - US Army Corps of Engineers (USACE) A 2016 Formerly Utilized Sites Remedial Action Program (FUSRAP) 

update.

05/17/2018 1

Internet - Washington State University (U.S. Transuranium 

and Uranium Registries)

No relevant documents identified. 04/08/2019 0

Internet - Y-12 Y-12 anecdotes including one on thorium production. 08/01/2018 1

Iowa State University Library An interview with Dr. Frank Spedding. 09/18/2013 1

Iron Mountain Storage Facility, Cranberry, PA Survey of control over source and special nuclear materials, National 

Distillers and Chemicals Corporation.

09/11/2006 1

Kansas City Plant Statement of Dr. Victor H. Reis before the subcommittee on Military 

Procurement Committee on National Security, US House of 

Representatives, radiological incidents, receipt of potentially 

contaminated parts, radiological surveys and air samples, operations 

reports, and dosimetry services.

03/04/2015 21

Kansas City Plant / SC&A Notes from the review of Kansas City Plant classified documents. 08/16/2013 1

Lawrence Berkeley National Laboratory (LBNL) Laboratory contracts 1948. 02/06/2007 1

Lawrence Berkeley National Laboratory (LBNL) / SC&A Long-range studies of uranium workers and Oak Ridge radiation 

worker population.

05/13/2009 1

Lawrence Livermore National Laboratory (LLNL) Project Pluto meeting minutes, a glove box incident report, 

determinations of possible excursion yields and exposure rates, 

feasibility of liquid material transfers, and the Rocky Flats body 

counter.

11/16/2017 11

Los Alamos National Laboratory (LANL) Excursions at the Oak Ridge criticality experiments facility, 

nonnuclear consolidation environmental assessment, polonium 

contamination at Pajarito, low-level mixed waste streams for the DOE 

Complex, corrected information on a plutonium shipment, a uranyl 

nitrate slurry problem, decontaminating plutonium from oralloy parts 

for Y-12, and radioactive waste disposal and related issues.

01/16/2018 11
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Los Alamos National Laboratory (LANL) - LAHDRA Waste minimization at a plutonium processing facility, a low-level 

complex-wide mixed waste report, and an environmental impact 

statement for the storage and disposition of weapons-usable fissile 

material.

11/30/2006 3

Mel Chew & Associates A 1994 radiation exposure summary, laboratory procedures for 

thorium analyses, individual and group exposure histories, fecal 

uranium measurements, the uranium in urine program, recycled 

uranium data spreadsheets, and plutonium urine results.

12/14/2014 62

Metals & Controls Corp Analysis of possible nuclear material losses and possible liabilities 

associated with present fuel manufacturing.

08/24/2004 1

MJW Proceedings of a short nuclear criticality safety course. 10/16/2003 1

Mound Museum Disposition of depleted salvage material, exposure to polonium from a 

neutron source, fabrication of weapon components, a shipment of 

irradiated bismuth slugs, polonium characteristic X-rays, polonium 

hazards, and correspondence concerning a lithium compound.

05/18/2010 12

National Archives and Records Administration (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, radiochemistry reports, shipments 

from Metal Hydrides to AEC facilities, shipping receipts, work done at 

Iowa State College, and handling fissionable material.

09/01/2015 135

National Archives and Records Administration (NARA) - 

Atlanta / SC&A

Decontamination of gloves. 09/26/2003 1

National Archives and Records Administration (NARA) -

Chicago

Fuel preparation for the ZPR-III Reactor. 06/12/2015 1

National Archives and Records Administration (NARA) -

College Park

Meteorological conditions, machining of uranium metal, 

accountability reports, thorium reports, researcher notes, Manhattan 

District history sections, and monthly status and progress reports.

03/11/2014 21
SEC-00250 07-17-19 Y-12 Plant

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Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

National Archives and Records Administration (NARA) -

Kansas City

Historical information from property insurance association on Niagara 

Falls Storage Site / African Metals leased areas, a survey of the 

Nuclear Chemicals and Metals Facility before and after a shipment to 

Y-12, radon emission data, TLD occupational exposure reports, and 

the 1995 transuranic waste baseline report.

07/11/2016 5

National Archives and Records Administration (NARA) -

Seattle

Material transfers and a continuous air monitor calibration. 08/23/2017 5

Nevada Test Site (NTS) The Y-12 electron beam welder and shipment of reactor fuel and waste 

from NTS to Y-12.

04/14/2008 2

New York State Archives A Manhattan District history section and waste disposal at Lake 

Ontario Ordnance Works.

03/19/2012 2

New York Department of Environmental Conservation Recovery of uranium from Sylvania scrap and disposal of special 

material under Contract AT(40-1)-2558.

07/31/2008 2

NIOSH Production and use of recycled uranium, 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, the evaluation of 

health physics problems in thorium processing, trip reports, AEC 

reports to Congress, documented communications, worker outreach 

meeting minutes, and recycled uranium processing at Fernald.

11/22/2017 55

NIOSH - Health Related Energy Research Branch (HERB) 

Library

Oxide conversion facility work history reports. 09/08/2003 1

NIOSH / SC&A BWXT-ORAU correspondence 2003-2005, recycled uranium project 

report, highly enriched uranium working group reports, Np-237 and U238 alloy radiation safety requirements, remarks on personnel 

monitoring at Y-12, technical basis document for the internal 

dosimetry program at Y-12, uranium urinalysis program, and a Y-12 

Complex description.

02/05/2009 16

NIOSH OCAS Claims Tracking System (NOCTS) A 1957 special separations logbook and a log entry regarding an Am241 lung burden.10/16/2018 2
SEC-00250 07-17-19 Y-12 Plant

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SRDB

Nuclear Regulatory Commission (NRC) Public Document 

Room

A trip report, the sixth intercomparison of nuclear accident dosimeters, 

the draft environmental assessment for treatment of low-level and 

mixed waste, in-vivo counts for two Kerr-McGee employees involved 

in a thorium explosion, and references to Y-12 in a NUMEC license 

renewal application.

08/15/2017 5

Oak Ridge Associated Universities (ORAU) Brief history of the Y-12 external monitoring program, correction 

factors for film badge data, 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, information on the calutron program for 

uranium enrichment, plutonium urinalysis results, health physics 

reports for buildings and departments, polonium urinalysis reports, 

uranium and plutonium urinalysis reports, individual employee 

bioassay reports, tritium urinalysis reports, Building 9805-1 tritium 

reports, and high dose investigation reports.

05/14/2012 230

Oak Ridge Associated Universities (ORAU) / Mel Chew & 

Associates

Tritium urinalysis reports. 05/14/2012 4

Oak Ridge Institute for Science and Education (ORISE) Data collection and validation for the Oak Ridge nuclear facilities 

mortality study.

06/11/2003 1

Oak Ridge Library for Dose Reconstruction Status report on Clinch River study, high-flux isotope reactor 

description, engineering development of hydraulic fracturing as a 

method for permanent disposal of radioactive wastes, contaminant 

releases, uranium releases, annual applied health physics reports, 

environmental levels of radioactivity, aerial radiological surveys, 

annual environmental reports, waste disposal reports, recovery of 

uranium from fiberglass air filters, incident reports, historical uranium 

releases, fallout measurements, material accountability reports, stack 

sampling, facility and department periodic reports, analysis of the 

1989 UF6 release, and worker mortality rates. 

08/15/2011 298
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SRDB

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, Y-12 film monitoring program, releases of thorium 

in Building 9204-1, 86-inch cyclotron target ruptures, area, equipment, 

and personnel contamination occurrence reports, periodic ORNL 

Division reports including material accountability, isotopic power 

materials, isotopes development center, and operations and individual 

dosimetry records. 

09/03/2015 289

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, history and 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, analysis of 

electronic personnel exposure data from Y-12, documented 

communications, technical basis documents, technical information 

bulletins, thorium air sample data spreadsheet, Y-12 quarterly health 

physics reports, in-vivo input and output radiation monitoring reports, 

quarterly health physics and industrial hygiene reports, annual body 

counter reports, an example of actinium and lead body counting 

reporting, and neutron dose from highly enriched uranium. 

03/28/2019 254
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SRDB

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 

environment, 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, 

technical basis for the Centralized External Dosimetry System, trip 

reports, waste disposal criteria, and Y-12 TLD results that include 

Paducah area dosimeters.

10/06/2006 13

Pantex Monitoring procedures for items received at Pantex. 07/19/2011 1

Personal Files – [Name redacted] The sixteenth through the twenty-first DOE annual reports of radiation 

exposure.

10/11/2006 6

Personal Files - [Name redacted] A DOE contractor health and mortality report. 04/06/2010 1

Personal Files - [Name redacted] Office of Oversight Radiological Protection task team reports. 07/16/2018 1

Portsmouth Gaseous Diffusion Plant Eighth Analytical Services Forum Paducah Gaseous Diffusion Plant, 

transfer of enriched uranium, and the neutron threshold detection 

project.

01/30/2013 3

Reactive Metals, Inc. (RMI) Historic radionuclide releases from Oak Ridge Operations facilities. 08/17/2006 1

Rocky Flats Environmental Technology Site (RFETS) The flammability and explosion potential of transuranic waste and 

audit responses.

08/31/2012 2

Sandia National Laboratories-Albuquerque Technical basis for workplace air monitoring of airborne radioactive 

material at Y-12, Ross Aviation shipment surveys and documents, the 

1991-1993 ORNL bioassay QC program, Webdose database external 

doses 2006-2008, and approval of the revised Radiological Control 

Manual.

09/09/2014 7

Savannah River Site (SRS) Dosimetry visitors cards, radiation survey log sheets, a trip report, 

material transfers, SRS monthly reports, the thoria fuel irradiation 

program, laboratory fume hood minimum acceptable face velocities, 

and the SRS response to the 1998 DOE Bioassay Enforcement 

Moratorium.

02/28/2019 14
SEC-00250 07-17-19 Y-12 Plant

78 of 81

Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

S. 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, recycled uranium mass balance project information, a trip 

report, criteria for acceptance of enriched uranium at Y-12, incident 

reports, unclassified thorium documents, special nuclear material 

licensing, and documented communications.

04/26/2011 18

SC&A / Atlanta NARA Thorium metal processes. 09/26/2003 1

SC&A / Idaho National Laboratory Environmental report, airborne radionuclide waste management 

information, a mercury shipment, a survey of waste management 

practices, and Idaho Chemical Processing Plant periodic reports.

06/24/2010 13

SC&A / Internet - DOE OpenNet Linking Legacies. 05/24/2017 1

SC&A / NIOSH The generation and flow of recycled uranium. 08/14/2003 1

SC&A / Y-12 Mobile lung counter data and fires and explosives investigations. 07/28/2010 2

Science Applications International Corporation (SAIC) Annual summaries of whole body radiation exposures to external 

penetrating radiation.

09/02/2004 9

Southern Illinois University Nuclear fuel fabrication, Oak Ridge site description, observations on 

uranium exposures, visit requests, and the transcript of day two of the 

fifty-sixth Advisory Board on Radiation and Worker Health meeting.

10/29/2008 8

University of Colorado Norlin Library A formal safety program cost/benefit study. 04/10/2006 1

University of Rochester Radiation Safety Office Return of uranium peroxide to Oak Ridge. 08/20/2008 1

University of Tennessee Library Creation of Clinton Engineer Works, a health physics report, health 

physics and exposure records, a calutron newspaper article, personnel 

monitoring records, the Biology Division Hot Laboratory, the 

decontamination of Building 9204-1, burial of Y-12 wastes, and a 

survey of Building 9206. 

10/11/2011 14
SEC-00250 07-17-19 Y-12 Plant 

79 of 81 

Data Capture Information General Description of Documents Captured Date Completed Uploaded to 

SRDB

Unknown Annual radiation dose reports, annual environmental reports, 

designation of race tracks by number Y-12 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.

02/10/2011 219

Unknown / SC&A Y-12 references in Linking Legacies and a DOE indoor radon study. 10/09/2003 2

Unknown / Y-12 The Y-12 outdoor scoping survey. 06/10/2004 1

United States Army Corps of Engineers (USACE) Lake Ontario Ordnance Works document search and remediation 

reports.

11/29/2007 2

United States Enrichment Corporation (USEC) A 1977 radiation termination report, the ERDAM 0525 annual 

occupational exposure reporting form, and a US Navy report on 

radioactive wastes.

10/06/2006 3

Weldon Spring Analysis of long term data on uranium in air. 11/29/2004 1

Westinghouse Site (MO) Accidental radiation excursion at Y-12, estimated lung exposure, invivo count results, and procedures and assignments for restricted 

personnel.

04/09/2009 7

Y-12 / SC&A Medical examination reports, occupational medical review reports, 

environmental pollution and control data, radiation exposure data, and 

Y-12 specifications for recycle material receipts. 

07/28/2010 5

TOTAL NA NA 5,067
SEC-00250 07-17-19 Y-12 Plant 

80 of 81 

Table A1-2: Database Searches for the Y-12 Plant

Database / Source Keywords / Phrases Hits Selected

Defense Technical Information Center (DTIC)

http://www.dtic.mil/dtic/

COMPLETED 03/26/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

14,950 6

DOE Hanford Declassified Document Retrieval System 

(DDRS) and Public Reading Room

http://reading-room.labworks.org/Catalog/Search.aspx

COMPLETED 04/05/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

4 1

DOE Legacy Management Considered Sites

https://www.lm.doe.gov/Considered_Sites/Summary/

COMPLETED 04/08/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

3,872 2

DOE National Nuclear Security Administration (NNSA) -

Nevada Site Office

https://nnsa.energy.gov/library

COMPLETED 04/01/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

1,468 4

DOE Noncompliance Tracking System 

https://appaccess.ntc.doe.gov/Authentication/Login?applica

tionID=1&returnURL=https%3a%2f%2fnts.ntc.doe.gov%2

fAuthentication%2fADFSSignIn

COMPLETED 10/04/2018

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

158 1

DOE Occurrence Reporting and Processing System 

https://www.energy.gov/ehss/policy-guidancereports/databases/occurrence-reporting-and-processingsystem

COMPLETED 10/04/2018

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

817 0

DOE OpenNet

http://www.osti.gov/opennet/advancedsearch.jsp

COMPLETED 04/05/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

3,882 133

DOE OSTI SciTech Connect

http://www.osti.gov/scitech/

COMPLETED 04/22/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

409,550 50

Energy Employees Claimant Assistance Project (EECAP)

http://www.eecap.org

COMPLETED 03/26/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

19 0

Google

http://www.google.com

COMPLETED 04/09/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

4,732,597,100 36

Health Physics Journal

http://journals.lww.com/health-physics/pages/default.aspx

COMPLETED 03/26/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

219 1
SEC-00250 07-17-19 Y-12 Plant 

81 of 81 

Database / Source Keywords / Phrases Hits Selected

Journal of Occupational and Environmental Health 

http://www.maneyonline.com/loi/oeh

COMPLETED 03/26/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

9 0

National Academies Press

http://www.nap.edu/

COMPLETED 04/08/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

15,124 0

National Service Center for Environmental Publications 

(NEPIS)

http://nepis.epa.gov/

COMPLETED 04/09/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

317 14

NRC ADAMS Reading Room

https://www.nrc.gov/reading-rm/adams.html#web-basedadams

COMPLETED 04/05/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

1,210 83

United States Army Corps of Engineers (USACE)

http://www.usace.army.mil/

COMPLETED 04/08/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

10 0

U.S. Transuranium & Uranium Registries 

http://www.ustur.wsu.edu/

COMPLETED 04/08/2019

Database search terms and Internet URL are available in the Excel file 

called “Y-12 Rev 02, 06-04-19”

29 0