ORAU TEAM

Dose Reconstruction

Project for NIOSH

Oak Ridge Associated Universities I Dade Moeller & Associates I MJW Corporation

Page 1 of 9

Document Title:

Rocky Flats Plant – Introduction

Document Number: ORAUT-TKBS-0011-1

Revision: 01

Effective Date: 11/30/2006

Type of Document: TBD

Supersedes: Revision 00

Subject Experts: Craig A. Little and Robert Meyer

Approval: Signature on File Approval Date: 11/15/2006

Robert Meyer, Document Owner

Approval: Signature on File Approval Date: 11/15/2006

John M. Byrne, Task 3 Manager

Concurrence: Signature on File Concurrence Date: 11/15/2006

Edward F. Maher, Task 5 Manager

Concurrence: Signature on File Concurrence Date: 11/16/2006

James P. Griffin, Deputy Project Director

Approval: Brant A. Ulsh Signature on File for Approval Date: 11/30/2006

James W. Neton, Associate Director for Science

 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-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 2 of 9

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION 

NUMBER DESCRIPTION

04/20/2004 00 New technical basis document for the Rocky Flats Plant –

Introduction. First approved issue. Initiated by Robert Meyer.

11/30/2006 01 Approved Revision 01 to incorporate responses to union comments. 

Added Section 1.2, Attributions and Annotations. Constitutes a total 

rewrite of the document. Incorporates internal formal review 

comments. This revision results in no change to the assigned dose 

and no PER is required. Training required: As determined by the 

Task Manager. Initiated by Robert Meyer.
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 3 of 9

TABLE OF CONTENTS

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

1.1 Purpose ...................................................................................................................................5

1.2 Scope.......................................................................................................................................6

1.3 Attributions and Annotations ....................................................................................................8

References ..........................................................................................................................................9
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 4 of 9

ACRONYMS AND ABBREVIATIONS

DOE U. S. Department of Energy

EEOICPA Energy Employees Occupational Illness Compensation Program Act of 2000

IREP Interactive RadioEpidemiological Program 

IMBA Integrated Modules for Bioassay Analysis

MDA minimum detectable activity 

NIOSH National Institute for Occupational Safety and Health

POC probability of causation

RFP Rocky Flats Plant

TBD technical basis document

U.S.C. United States Code

§ section or sections
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 5 of 9

1.1 PURPOSE

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 historic 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

As noted above, the statute 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 contains an exclusion with respect to the Naval Nuclear Propulsion Program, 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 dosimetry monitoring results are considered valid for use in 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:

] 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) define “performance of duty” for DOE employees 

with a covered cancer or restrict the “duty” to nuclear weapons work.

• Radiation from naturally occurring radon present in conventional structures

• Radiation from diagnostic X-rays received in the treatment of work-related injuries

 1 The U.S. Department of Labor is ultimately responsible under the EEOICPA for determining the POC.
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 6 of 9

This Site Profile provides specific information about documentation of historical practices at the Rocky 

Flats Plant (RFP). Dose reconstructors can use this Site Profile to evaluate internal and external 

dosimetry data for unmonitored and monitored workers and to serve as a supplement to, or substitute 

for, individual monitoring data. This document contains technical basis information the Oak Ridge 

Associated Universities (ORAUT) Team can use to evaluate the total occupational radiation dose for 

EEOICPA claimants.

This document also provides supporting technical data to evaluate, with assumptions that are 

favorable to claimants, the total RFP occupational radiation dose that can reasonably be associated 

with a worker’s radiation exposure. This dose results from exposure to external and internal radiation 

sources in RFP facilities, occupationally required diagnostic X-ray examinations, and onsite 

environmental releases. 

Doses are evaluated using the NIOSH Interactive RadioEpidemiological Program (IREP) and 

Integrated Modules for Bioassay Analysis (IMBA) computer programs. Information on measurement 

uncertainties is an integral component of the NIOSH approach. This document describes the 

evaluation of uncertainty for RFP exposure and dose records.

1.2 SCOPE

The Site Profile consists of five TBDs in addition to this Introduction: Site Description, Occupational 

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

External Dosimetry.

The Site Description TBD (ORAUT 2004a) describes RFP facilities and processes used in the 

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

weapons program; these operations included production of weapons components. This TBD contains 

documentation to assist in the evaluation of worker dose from RFP operations and processes.

In March 1951, the U.S. Atomic Energy Commission announced its decision to build RFP in Colorado, 

and groundbreaking occurred in July 1951. From the beginning, the Plant was a manufacturing 

facility. The primary mission and general activities at the Plant remained essentially the same from 

the time it opened until 1989, when DOE suspended plutonium operations. RFP had two major 

missions – production of plutonium triggers (or pits) for nuclear weapons, and processing of weapons 

for plutonium recovery. Early designs that were solid units made mostly of uranium gave way to a 

plutonium pit design in the mid-1950s. Plutonium pits or triggers are components of fission bombs, 

and can be used to initiate the fusion reaction in hydrogen bombs. Plutonium was received from the 

DOE Savannah River and Hanford sites and from retired warheads and residues.

Parts were formed and machined from plutonium, uranium, beryllium, stainless steel, and other 

materials. Plutonium and uranium recovery and waste handling facilities were present on the site to 

handle radioactive wastes produced in these processes.

The Occupational Medical Dose TBD (ORAUT 2004b) provides information about doses received by 

individual workers from X-rays that were required as a condition of employment. Entrance, exit, and 

periodic physical examinations were performed on all employees as part of the requirements for 

employment at RFP. These examinations could include radiographic examinations of the lungs and, 

for some employees, possible radiographs of the lumbar spine. 

Doses to exposed organs from the chest X-rays have also been calculated. The calculated dose 

takes into account the uncertainty associated with machine type, examination frequency, and job 
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 7 of 9

classification. This TBD contains tables of the doses received by the various organs in the body for 

convenient reference by dose reconstructors.

Occupational environmental dose (described in ORAUT 2004c) is the dose workers receive when 

working outside buildings, from inhalation of or direct exposure to radioactive materials in the air, and 

from direct exposure to radionuclides incorporated in the soil.

Internal dose can result from inhalation of radioactive materials, and whole- or partial-body external 

dose can result from deposited radionuclides or submersion in a cloud of radioactive material. 

Although plutonium (239/240Pu, 241Pu) is the primary material of concern for offsite exposures, tritium, 

natural thorium, enriched uranium, depleted uranium, and 241Am were other radionuclides of possible 

concern identified in historical exposure studies of the public. 

External doses to workers from onsite ambient radiation levels are determined from measurements 

reported in and estimated from site annual environmental reports.

The Occupational Internal Dosimetry TBD (ORAUT 2005) discusses the RFP internal dosimetry 

program and develops estimates of potential intakes. Workers at RFP had the potential to take in 

plutonium, americium, enriched uranium, and depleted uranium, as well as smaller quantities of other 

radionuclides. This TBD describes available source term information including isotopic composition, 

solubility, and particle size (where applicable) for plutonium, americium, enriched uranium, depleted 

uranium, and other radionuclides. Site-specific internal dosimetry information for other radionuclides 

such as tritium, thorium, curium, and neptunium is very limited. 

The primary modes of intake have been chronic or acute inhalation, or via breaks in the skin 

(wounds). Urinalyses provide data reflecting such intakes. Lung counts provide estimates of

radionuclide quantities present in the lungs. The TBD discusses these two data sets in detail, 

including history, sensitivity, and pertinent methods. 

The internal exposure record for a specific worker consists of bioassay data and reports of 

involvement in incidents, accidents, or special situations. The TBD contains samples of records and 

reports that provide explanations of terms important to dosimetry.

The TBD discusses minimum detectable activities (MDAs), analytical methods, and reporting 

protocols in relation to urinalysis methods for the radionuclides encountered at RFP. Those 

parameters changed over the years for each radionuclide. The TBD discusses details of these 

variables.

The TBD also discusses MDAs, analytical methods, and reporting protocols for in vivo lung counts for 

X- and gamma-emitting radionuclides. The in vivo measurement equipment and techniques, which 

were developed in the late 1950s, have been in regular use at RFP since 1964. The TBD contains a 

discussion of the lung counter systems including 241Am-specific MDAs and reporting levels for the 

various periods during which these parameters changed. It provides detailed information to assist 

dose reconstructors in interpreting data encountered in worker records.

The Occupational External Dosimetry TBD (ORAUT 2004d) describes the methods, concepts, and 

evolution of systems for measuring occupational external dose to workers. It provides supporting 

technical data to evaluate, with assumptions that are favorable to claimants, external RFP 

occupational doses associated with worker radiation exposures covered under the EEOICPA. These 

doses include occupational external exposures in RFP facilities and onsite exposures to RFP 

environmental releases. The TBD evaluates unmonitored and monitored worker exposure and 
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 8 of 9

missed dose. Consistent with NIOSH implementation guidelines, it provides guidance on the 

adjustment of occupational external recorded dose in light of the best information available.

1.3 ATTRIBUTIONS AND ANNOTATIONS

None.
Document No. ORAUT-TKBS-0011-1 Revision No. 01 Effective Date: 11/30/2006 Page 9 of 9

REFERENCES

ORAUT (Oak Ridge Associated Universities Team), 2004a, Technical Basis Document for the Rocky 

Flats Plant – Site Description, ORAUT-TKBS-0011-2, Rev. 00, Oak Ridge, Tennessee, 

January 10.

ORAUT (Oak Ridge Associated Universities Team), 2004b, Technical Basis Document for the Rocky 

Flats Plant – Occupational Medical Dose, ORAUT-TKBS-0011-3, Rev. 00, Oak Ridge, 

Tennessee, February 9.

ORAUT (Oak Ridge Associated Universities Team), 2004c, Technical Basis Document for the Rocky 

Flats Plant – Occupational Environmental Dose, ORAUT-TKBS-0011-4, Rev. 01, Oak Ridge, 

Tennessee, June 29.

ORAUT (Oak Ridge Associated Universities Team), 2004d, Technical Basis Document for Rocky 

Flats Plant – Occupational External Dosimetry, ORAUT-TKBS-0011-6, Rev. 00, Oak Ridge, 

Tennessee, January 20.

ORAUT (Oak Ridge Associated Universities Team), 2005, Technical Basis Document for the Rocky 

Flats Plant – Occupational Internal Dose, ORAUT-TKBS-0011-5, Rev. 00 PC-1, Oak Ridge, 

Tennessee, December 13.