ORAU TEAM

Dose Reconstruction

Project for NIOSH

Oak Ridge Associated Universities I Dade Moeller I MJW Technical Services

Page 1 of 9

DOE Document Review 06/05/2013

Document Title:

Weldon Spring Plant - Introduction

Document Number: ORAUT-TKBS-0028-1

Revision: 01

Effective Date: 05/24/2013

Type of Document: TBD

Supersedes: Revision 00 PC-1

Subject Expert(s): David P. Harrison

Approval: Signature on File Approval Date: 05/21/2013

David P. Harrison, Document Owner

Concurrence: Signature on File Concurrence Date: 05/22/2013

John M. Byrne, Objective 1 Manager

Concurrence: Signature on File Concurrence Date: 05/21/2013

Edward F. Maher, Objective 3 Manager

Concurrence: Vickie S. Short Signature on File for Concurrence Date: 05/22/2013

Kate Kimpan, Project Director

Approval: Signature on File Approval Date: 05/24/2013

Stuart L. Hinnefeld, Director DCAS

New Total Rewrite Revision Page Change

FOR DOCUMENTS MARKED AS A TOTAL REWRITE, REVISION, OR PAGE CHANGE, REPLACE THE PRIOR 

REVISION AND DISCARD / DESTROY ALL COPIES OF THE PRIOR REVISION.
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 2 of 9

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION 

NUMBER DESCRIPTION

06/28/2005 00 Technical basis document for the Weldon Spring Plant – Introduction. 

Incorporates internal review comments, responses to NIOSH 

comments, and an additional change per a NIOSH comment. First 

approved issue. Training is not required. Initiated by Robert Meyer.

06/30/2008 00 PC-1 Approved page change revision initiated to eliminate reference to a 

user’s guide on page 10 in Section 1.2, which was never published 

due to a change in policy. Added an Attributions and Annotations 

Section on page 10, updated NIOSH required language on page 5 in 

Section 1.1, and ORAU team references on pages 8 and 11. Now 

uses term, “favorable to claimant” on pages 6, 9, and 10 in Sections 

1.1 and 1.2. No sections were deleted. Incorporates formal internal 

review comments. No changes were needed as a result of NIOSH 

formal review. Training required: As determined by the Task 

Manager. Initiated by Melton H. Chew. Approval: 

Signature on File for 06/11/2008

Melton H. Chew, Document Owner

Signature on File 06/11/2008

John M. Byrne, Task 3 Manager

Signature on File 06/11/2008

Edward F. Maher, Task 5 Manager

Signature on File 06/13/2008

Kate Kimpan, Project Director

Signature on File 06/30/2008

James W. Neton, Associate Director for Science

05/24/2013 01 Revision implemented according to guidance from ORAUT-PROC0031, Rev. 04. Section 1.1: Replaced introductory text with updated 

template language. Added Section 1.1.1, “Purpose,” and changed 

heading from “Site Profile Description” to “Scope” for Section 1.1.2. 

Minor technical editing conducted for Section 1.2. Deleted 

repetitious details and results that appear in subsequent sections of 

the Site Profile from Sections 1.3 through 1.6. Updated the 

Acronyms and Abbreviations and the References sections. No 

sections were deleted. No changes occurred as a result of formal 

internal review. Incorporates formal NIOSH review comments. 

Constitutes a total rewrite of the document. Training required: As 

determined by the Objective Manager. Initiated by David P. 

Harrison.
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 3 of 9

TABLE OF CONTENTS

SECTION TITLE PAGE

Acronyms and Abbreviations ...............................................................................................................4

1.1 Introduction.................................................................................................................................5

1.1.1 Purpose...........................................................................................................................6

1.1.2 Scope..............................................................................................................................6

1.2 Site Description...........................................................................................................................6

1.3 Occupational Medical Dose ........................................................................................................7

1.4 Occupational Environmental Dose ..............................................................................................7

1.5 Occupational Internal Dosimetry .................................................................................................8

1.6 Occupational External Dosimetry ................................................................................................8

1.7 Attributions and Annotations .......................................................................................................8

References ..........................................................................................................................................9
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 4 of 9

ACRONYMS AND ABBREVIATIONS

AEC U.S. Atomic Energy Commission

CFR Code of Federal Regulations

DOE U.S. Department of Energy

DOL U.S. Department of Labor 

EEOICPA Energy Employees Occupational Illness Compensation Program Act of 2000

NIOSH National Institute for Occupational Safety and Health

ORAU Oak Ridge Associated Universities

POC probability of causation

TBD technical basis document

U.S.C. United States Code

WSCP Weldon Spring Chemical Plant

WSP Weldon Spring Plant

WSQ Weldon Spring Quarry

WSRP Weldon Spring Raffinate Pits

§ section or sections
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 5 of 9

1.1 INTRODUCTION

Technical basis documents and site profile documents are not official determinations made by the 

National Institute for Occupational Safety and Health (NIOSH) but are rather general working 

documents that provide historical background information and guidance to assist in the preparation of 

dose reconstructions at particular sites or categories of sites. They will be revised in the event 

additional relevant information is obtained about the affected site(s). These documents may be used 

to assist NIOSH staff in the completion of the individual work required for each dose reconstruction.

In this document the word “facility” is used as a general term for an area, building, or group of 

buildings that served a specific purpose at a site. It does not necessarily connote an “atomic weapons 

employer facility” or a “Department of Energy [DOE] facility” as defined in the Energy Employees 

Occupational Illness Compensation Program Act [EEOICPA; 42 U.S.C. § 7384l(5) and (12)]. 

EEOICPA defines a DOE facility as “any building, structure, or premise, including the grounds upon 

which such building, structure, or premise is located ... in which operations are, or have been, 

conducted by, or on behalf of, the Department of Energy (except for buildings, structures, premises, 

grounds, or operations ... pertaining to the Naval Nuclear Propulsion Program)” [42 U.S.C. § 

7384l(12)]. Accordingly, except for the exclusion for the Naval Nuclear Propulsion Program noted 

above, any facility that performs or performed DOE operations of any nature whatsoever is a DOE 

facility encompassed by EEOICPA.

For employees of DOE or its contractors with cancer, the DOE facility definition only determines 

eligibility for a dose reconstruction, which is a prerequisite to a compensation decision (except for 

members of the Special Exposure Cohort). The compensation decision for cancer claimants is based 

on a section of the statute entitled “Exposure in the Performance of Duty.” That provision [42 U.S.C. § 

7384n(b)] says that an individual with cancer “shall be determined to have sustained that cancer in the 

performance of duty for purposes of the compensation program if, and only if, the cancer ... was at 

least as likely as not related to employment at the facility [where the employee worked], as 

determined in accordance with the POC [probability of causation1

] guidelines established under 

subsection (c) ...” [42 U.S.C. § 7384n(b)]. Neither the statute nor the probability of causation 

guidelines (nor the dose reconstruction regulation, 42 C.F.R. Pt. 82) restrict the “performance of duty” 

referred to in 42 U S. C. § 7384n(b) to nuclear weapons work (NIOSH 2010).

The statute also includes a definition of a DOE facility that excludes “buildings, structures, premises, 

grounds, or operations covered by Executive Order No. 12344, dated February 1, 1982 (42 U.S.C. 

7158 note), pertaining to the Naval Nuclear Propulsion Program” [42 U.S.C. § 7384l(12)]. While this 

definition excludes Naval Nuclear Propulsion Facilities from being covered under the Act, the section 

of EEOICPA that deals with the compensation decision for covered employees with cancer [i.e., 42 

U.S.C. § 7384n(b), entitled “Exposure in the Performance of Duty”] does not contain such an 

exclusion. Therefore, the statute requires NIOSH to include all occupationally-derived radiation 

exposures at covered facilities in its dose reconstructions for employees at DOE facilities, including 

radiation exposures related to the Naval Nuclear Propulsion Program. As a result, all internal and 

external occupational radiation exposures are considered valid for inclusion in a dose reconstruction. 

No efforts are made to determine the eligibility of any fraction of total measured exposure for inclusion 

in dose reconstruction. NIOSH, however, does not consider the following exposures to be 

occupationally derived (NIOSH 2010):

• Background radiation, including radiation from naturally occurring radon present in 

conventional structures

 1 The U.S. Department of Labor (DOL) is ultimately responsible under the EEOICPA for determining the POC.
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 6 of 9

• Radiation from X-rays received in the diagnosis of injuries or illnesses or for therapeutic 

reasons

1.1.1 Purpose

The purpose of this TBD is to introduce the Weldon Spring Plant (WSP) Site Profile, which contains 

technical basis information for the evaluation of the total occupational dose for EEOICPA claimants 

who were employed at WSP.

1.1.2 Scope

The Site Profile consists of this Introduction and five major TBDs: Site Description, Occupational 

Medical Dose, Occupational Environmental Dose, Occupational Internal Dosimetry, and Occupational 

External Dosimetry. Some of these have attachments that provide critical data for dose 

reconstructors. 

1.2 SITE DESCRIPTION

The WSP Site Description TBD (ORAUT 2013a) discusses facilities and processes that were used in 

the processing of uranium concentrates and other uranium compounds from 1957 through 1966. 

WSP operations played an important role in the development of U.S. nuclear weapons. These 

operations focused on processing uranium and thorium from feed stocks to metal and intermediate 

products for use at other facilities. This TBD contains documentation to assist in the evaluation of 

worker dose from WSP operations and processes.

Site History and Operations

In April 1941, the War Department acquired 17,232 acres surrounding what is now the Weldon Spring

Chemical Plant (WSCP) as the site for an explosives production facility known as the Weldon Spring 

Ordnance Works. By 1949, the ordnance works had been shut down and all but about 2,000 acres 

had been transferred to the State of Missouri and the University of Missouri. 

In 1956, approximately 220 acres of the former Ordnance Works were transferred to the U.S. Atomic 

Energy Commission (AEC) for construction and operation of a Feed Materials Plant (the WSCP) to 

process uranium and thorium ore concentrates; this plant operated from 1957 through 1966. This Site 

Profile refers to the raffinate pits that were originally part of the WSCP as the Weldon Spring Raffinate 

Pits (WSRP) because they were managed separately in the postoperational period. In 1958, a 9-acre 

quarry site was transferred to the AEC; this is referred to as the Weldon Spring Quarry (WSQ). 

In August 1967, the WSCP was returned to U.S. Army control for construction of an herbicide 

production facility. However, the AEC retained custody of the WSQ and the WSRP. In 1985, DOE

(an AEC successor agency) regained responsibility for the WSCP and began site characterization and 

remediation. The quarry was placed on the National Priorities List in 1987; the listing was expanded 

to include the chemical plant area and associated waste storage areas in 1989. 

Before remediation, there were four periods of the WSP site and WSCP history: 

1. Plant acquisition and development from 1954 to 1957,

2. Operations from 1957 to 1966,

3. Initial cleanup from 1967 to 1969, and 

4. Maintenance from 1969 to 1985. 

The periods of concern for this Site Profile are those during which DOE and its predecessor agencies 

(AEC until 1975 and the Energy Research and Development Administration until 1979) had 
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 7 of 9

contractors at some or all of the WSP sites and facilities. These include the operations period (1957 

through 1966) and the monitoring and remediation periods (1975 to present). The monitoring period, 

from 1975 through 1984, applies only to the WSRP and WSQ because DOE did not assume control of 

the WSCP until 1985. Part 2 of this Site Profile contains a more detailed description of these 

activities.

During its operation by the Uranium Division of Mallinckrodt Chemical Works from 1957 to 1966, the 

WSCP processed four types of nuclear material (DOE 1986, pp. 13–14):

• Natural uranium was received as ore concentrates that were refined to extract the uranium, 

which was converted to various compounds and metal forms and shipped off the site. The 

processing of natural uranium was a continuous operation during the life of the Plant. 

• Uranium depleted in the 235U isotope below its natural isotopic abundance ratio was received 

and processed on an intermittent basis. This form of uranium was used primarily in product 

development activities and flow sheet improvements. Its use was confined primarily to pilot 

plant activities. 

• Uranium enriched to 1% or less 235U by weight was received and processed on an intermittent 

basis. This form of uranium was typically received in scrap metal or residues. The uranium 

contents were recovered, processed to various chemical forms, and shipped off the site. 

• Natural thorium was typically received in either a nitrate or oxide form and processed on an 

intermittent batch basis in the refinery and oxide production and firing systems.

1.3 OCCUPATIONAL MEDICAL DOSE

The WSP Occupational Medical Dose TBD (ORAUT 2013b) provides information about doses 

individual workers received from X-rays that were required as a condition of employment. Available 

information about the X-ray examination frequency, equipment, and techniques is provided in Part 3 

of this Site Profile. The TBD provides calculated organ dose estimates from occupational X-ray 

examinations that were administered at WSP from 1955 through 1966 (pre-1970), 1970 to 1985, and 

after 1985 using default dose estimates from ORAUT-OTIB-0006, Dose Reconstruction from 

Occupational Medical X-Ray Procedures (ORAUT 2011). Doses to other exposed organs from chest 

X-ray examinations have been calculated. The calculated doses take into account the uncertainty 

associated with machine type, examination frequency, and job classification. The TBD presents 

doses to organs in the body in tabular form for more convenient reference by dose reconstructors.

1.4 OCCUPATIONAL ENVIRONMENTAL DOSE

The WSP Occupational Environmental Dose TBD (ORAUT 2013c) considers doses that workers 

received while on the site but outside buildings; these typically result from inhalation of or direct 

exposure to radioactive materials in the air and from direct exposure to radionuclides in the soil. 

Part 4 of this Site Profile contains information necessary to estimate internal environmental dose and 

includes sections that discuss the radionuclides of concern, source terms (release rates) for 

radionuclides potentially significant to internal environmental dose, and available air (particulate 

radionuclides and radon) and external ambient monitoring data. These doses have been reported for 

the WSRP, WSCP, and WSQ areas in remedial investigations that supported the Comprehensive 

Environmental Response, Compensation, and Liability Act (CERCLA) process and in site-wide annual 

reports, and as a result of other radiological surveys. Airborne particulate and radon concentration 

data, normalized concentrations of radionuclides in soil, and estimated site-wide maximum annual 

inhalation intakes and ambient onsite dose at WSP are provided.
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 8 of 9

1.5 OCCUPATIONAL INTERNAL DOSIMETRY

The WSP Occupational Internal Dosimetry TBD (ORAUT 2013d) discusses the internal dosimetry 

program and develops estimates of potential intakes in accordance with OCAS-IG-002, Internal Dose 

Reconstruction Implementation Guideline (NIOSH 2002). Internal radiation dose is the dose to a 

worker from deposition of radionuclides in the body. Such deposition can occur as a result of 

inhalation of radionuclides in airborne dust, incidental ingestion of radionuclides, and intake through 

intact skin or wounds. 

Information on the source term for dosimetrically significant radionuclides at WSP, in vitro and in vivo

measurements, air monitoring, and an assessment of radionuclide intakes are presented in Part 5 of 

this Site Profile. Details for solubility classification, absorption type, and particle size are also 

presented. Available WSP data include in vitro data for uranium and in vivo data for thorium. 

Descriptions of the routine and special sampling programs, reporting levels, minimal detectable 

activities, interferences and uncertainties, reporting formats and codes, and work group (cost center

or job title) information are discussed. Extensive air monitoring was conducted during the operational 

period and summary results of a series of dust studies are presented in tables for use by the dose 

reconstructors. Intake data are presented in tabular form for all periods.

1.6 OCCUPATIONAL EXTERNAL DOSIMETRY

The WSP Occupational External Dosimetry TBD (ORAUT 2013e) describes methods and concepts 

for measuring occupational external dose to workers in accordance with OCAS-IG-001, External Dose 

Reconstruction Implementation Guideline (NIOSH 2007). This TBD provides technical data that dose 

reconstructors can use to evaluate, with favorable to claimant assumptions, external occupational 

doses that can reasonably be associated with worker radiation exposures. 

Part 6 of this Site Profile provides an overview of external dosimetry, information to interpret external 

dosimetry records, and a review of site administrative practices for recorded beta (skin) and gamma 

(deep) doses. Available information for badge assignment and exchange frequencies for the WSP is 

presented. Data tables are provided for workplace radiation fields at WSP including average gamma 

and beta dose, default photon energy distribution for WSP materials, and energy distribution by WSP 

building or area. The minimal neutron exposure potential at WSP is addressed. Dose conversion 

factors, potential maximum annual missed dose, and minimum dosimeter detection limits are 

tabulated for both photons and electrons. Other topics include dose record discrepancy guidance and 

favorable to the claimant instructions for missing entries in the records. Details are presented for 

calibration practices, uncertainty for film and thermoluminescent dosimetry systems, guidance for zero 

readings, unmonitored energy ranges, and angular dependence.

1.7 ATTRIBUTIONS AND ANNOTATIONS

All information requiring identification was addressed via references integrated into the reference 

section of this document.
Document No. ORAUT-TKBS-0028-1 Revision No. 01 Effective Date: 05/24/2013 Page 9 of 9

REFERENCES

DOE (U. S. Department of Energy), 1986, Historical Nuclear Materials Balance Report for the Former 

AEC-Owned Weldon Spring Chemical Plant, Weldon Spring, Missouri, DOE/OR-872, Oak 

Ridge Operations Office, July. [SRDB Ref ID: 8252]

NIOSH (National Institute for Occupational Safety and Health), 2002, Internal Dose Reconstruction 

Implementation Guideline, OCAS-IG-002, Rev. 0, Office of Compensation Analysis and 

Support, Cincinnati, Ohio.

NIOSH (National Institute for Occupational Safety and Health), 2007, External Dose Reconstruction 

Implementation Guideline, OCAS-IG-001, Rev. 3, Office of Compensation Analysis and 

Support, Cincinnati, Ohio.

NIOSH (National Institute for Occupational Safety and Health), 2010, Radiation Exposures Covered 

for Dose Reconstructions Under Part B of the Energy Employees Occupational Illness 

Compensation Program Act, DCAS-IG-003, Rev. 01, Division of Compensation Analysis and 

Support, Cincinnati, Ohio, October.

ORAUT (Oak Ridge Associated Universities Team), 2011, Dose Reconstruction from Occupational

Medical X-Ray Procedures, ORAUT-OTIB-0006, Rev. 04, Oak Ridge, Tennessee, June 20.

ORAUT (Oak Ridge Associated Universities Team), 2013a, Weldon Spring Plant–Site Description, 

ORAUT-TKBS-0028-2, Rev. 01, Oak Ridge, Tennessee, May 21.

ORAUT (Oak Ridge Associated Universities Team), 2013b, Weldon Spring Plant–Occupational 

Medical Dose, ORAUT-TKBS-0028-3, Rev. 01, Oak Ridge, Tennessee, January 30.

ORAUT (Oak Ridge Associated Universities Team), 2013c, Weldon Spring Plant–Occupational 

Environmental Dose, ORAUT-TKBS-0028-4, Rev. 01, Oak Ridge, Tennessee, May 17.

ORAUT (Oak Ridge Associated Universities Team), 2013d, Weldon Spring Plant–Occupational 

Internal Dose, ORAUT-TKBS-0028-5, Rev. 02, Oak Ridge, Tennessee, May 21.

ORAUT (Oak Ridge Associated Universities Team), 2013e, Weldon Spring Plant–Occupational 

External Dose, ORAUT-TKBS-0028-6, Rev. 01, Oak Ridge, Tennessee, February 6.