ORAU TEAM

Dose Reconstruction

Project for NIOSH

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

Page 1 of 14

Document Title:

K-25 Site – Site Description

Document Number: ORAUT-TKBS-0009-2 

Revision: 01

Effective Date: 10/04/2006

Type of Document: TBD

Supersedes: Revision 00

Subject Expert: Paul A. Szalinski

Approval: Signature on File Approval Date: 09/26/2006

Paul A. Szalinski, Document Owner

Approval: Signature on File Approval Date: 09/26/2006

John M. Byrne, Task 3 Manager

Concurrence: Signature on File Concurrence Date: 09/29/2006

Edward F. Maher, Task 5 Manager

Concurrence: Signature on File Concurrence Date: 10/03/2006

Kate Kimpan, Project Director

Approval: Brant A. Ulsh Signature on File for Approval Date: 10/04/2006

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-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 2 of 14

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION

NUMBER DESCRIPTION

09/10/2003 00-A New Technical Basis Document for the K-25 Site – Site Description. 

Initiated by Joseph Alvarez.

12/24/2003 00-B Incorporates DOL comments. Initiated by Joseph Alvarez.

01/12/2004 00 First approved issue. Initiated by Joe Alvarez.

10/04/2006 01 Approved issue of Revision 01. Revised the Introduction to include 

required language by NIOSH. Added Purpose and Scope sections. 

Deleted unnecessary Figure 2.1-1 in Section 2.2. Responded to 

Worker Outreach comments 22 and 24. No further changes 

occurred as a result of formal internal review. No changes were 

required due to the K25 Worker Outreach SPFPA and IGUA Worker 

Outreach meeting held on April 5, 2006 or K25 Worker Outreach 

PACE Local 5-288 and Pace International Union Worker Outreach 

meeting held on April 6, 2006. 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 Paul A. Szalinski. 
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 3 of 14

TABLE OF CONTENTS

SECTION TITLE

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

PAGE

4

2.1 Introduction ..............................................................................................................................5

 2.1.1 Purpose .........................................................................................................................6

 2.1.2 Scope.............................................................................................................................6

2.2 Site Activities and Processes ...................................................................................................6

2.2.1 K-25 Processing History.................................................................................................8

 2.2.2 Facilities and Support Locations.....................................................................................9

References ........................................................................................................................................12

Glossary ............................................................................................................................................13

LIST OF TABLES

TABLE TITLE

2-1 Solubility class of RU radionuclides........................................................................................

PAGE

14

2-2 K-25 radiological hazards by area.......................................................................................... 14
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 4 of 14

ACRONYMS AND ABBREVIATIONS

AVLIS Atomic Vapor Laser Isotope Separation

DOE U.S. Department of Energy

EEOICPA Energy Employees Occupational Illness Compensation Program Act of 2000

ETTP East Tennessee Technology Park

IMBA Integrated Modules for Bioassay Analysis

IREP Interactive RadioEpidemiological Program

NIOSH National Institute for Occupational Safety and Health

ORAU Oak Ridge Associated Universities

ORGDP Oak Ridge Gaseous Diffusion Plant

PGDP Paducah Gaseous Diffusion Plant

POC probability of causation

PWMP Pond Waste Management Project

RU recycled uranium

TBD technical basis document

TRU transuranic

TSCA Toxic Substances Control Act

U.S.C. United States Code

§ section or sections
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 5 of 14

2.1 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 for particular sites or categories of sites. The documents 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 POC 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

 

1 The U.S. Department of Labor is ultimately responsible under the EEOICPA for determining the POC. 
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 6 of 14

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

2.1.1

The purpose of this section is to provide a profile for the Oak Ridge Gaseous Diffusion Plant 

(ORGDP), also called K-25, that contains technical basis information used by the Oak Ridge 

Associated Universities (ORAU) Team to evaluate the total occupational dose for EEOICPA 

claimants.

Purpose

2.1.2

K-25 operations played an important role in the U.S. nuclear weapons program (DOE 1997). K-25 

processes included uranium enrichment in the isotope uranium-235 (235U), radiochemical processing, 

uranium recycling, and waste management. This TBD contains supporting documentation to assist in 

the evaluation of worker dose from these processes using the methodology described in NIOSH 

OCAS-IG-001, External Dose Reconstruction Implementation Guideline (NIOSH 2002a) and OCASIG-002, Internal Dose Reconstruction Implementation Guideline (NIOSH 2002b). 

Scope

Methods and concepts of measuring radiation exposure to workers have evolved since the beginning 

of K-25 operations in 1945. An objective of this document is to provide supporting technical data to 

evaluate, with assumptions favorable to claimants, the total K-25 occupational dose that can 

reasonably be associated with worker radiation exposure as covered under the EEOICPA legislation. 

This dose includes occupational external and internal exposure in K-25 facilities, K-25 occupationally 

required diagnostic X-ray examinations, and onsite exposure to K-25 and other Oak Ridge 

Reservation environmental releases. The documentation addresses evaluation of unmonitored and 

monitored worker exposure and missed dose. Consistent with NIOSH implementation guidelines, this 

document identifies how to adjust the historical occupational dose to account for current scientific 

methods and protection factors.

“This Site Profile can be a tool when performing dose reconstructions for K-25 workers. The 

Integrated Modules for BiioAssay Analysis (IMBA) computer code is a tool useful for internal dose 

calculations. Information on measurement uncertainties is an integral component of the NIOSH 

approach. This document describes how to evaluate uncertainty associated with K-25 exposure and 

dosimetry records.”

The following sections describe the facilities and processes, historical information related to worker 

internal and external exposures, and environmental data for use when actual monitoring data are 

unavailable. The attachments to this TBD contain critical data and tables required for individual 

worker dose reconstructions. The attachments should suffice as a standalone document for dose 

reconstruction. Additional details, if necessary, are in the main body of the text.

2.2 SITE ACTIVITIES AND PROCESSES

The dates of operation of the K-25 facilities and activities described below are from Recycled Uranium 

Mass Balance Project Oak Ridge Gaseous Diffusion Plant Site Report (BJC and Haselwood 

Enterprises 2000).

The K-25 Site, now known as the East Tennessee Technology Park (ETTP), processed thousands of 

tons of uranium through diffusion cascades for more than 40 years. The vast majority of the uranium 

was extracted and purified from ore, but some was recycled material obtained from spent reactor fuel.
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 7 of 14

The primary K-25 areas that enriched 235U using the gaseous diffusion process include Cascade 

Buildings K-25, K-27, K-29, K-31, K-33, K-413, and K-631. Uranium was initially processed in series 

operation in Buildings K-25, K-27, and K-29. Buildings K-31 and K-33 were later placed in series 

operations with the existing cascade. When the enrichment process was active, the uranium in these 

areas was almost exclusively in the form of uranium hexafluoride (UF6).

The uranium processed in these areas originated both from natural ores and recycled uranium 

products. The uranium feed materials, whether natural or recycled uranium, were purified before 

reaching K-25 and were chemically identical. Various natural sources were used but the uranium 

feed material was not source-dependent. The recycled uranium contained trace amounts of activation 

and fission products that were not completely removed by the recovery and purification processes. 

The recycled feed material could have varied somewhat depending upon both time in the reactor and 

process of recovery. 

Processing of recycled uranium from spent reactor fuel was intermittent, with campaigns conducted in 

1952 to 1964, 1969 to 1974, and 1976 and 1977. Virtually all of the recycled uranium came from 

plutonium production reactors at the Hanford and Savannah River Sites, with little from power or 

demonstration reactors.

The material recycled from reprocessed reactor fuels contained trace quantities of fission products 

and transuranic (TRU) elements formed during irradiation of the fuels. Most of these impurities were 

removed during chemical processing of the fuels. Because fluorinated compounds of the elements in 

question have limited volatility, much of the impurity activity initially present remained in the feed 

cylinders or was deposited in the cascade equipment very close to the feed point. However, trace 

quantities passed through the chemical and physical separations to contaminate the diffusion 

cascades.

Process operations primarily resulted in 234U, 235U, and 238U contamination. Characterization of the 

recycled uranium included in the Recycled Uranium Mass Balance Project Oak Ridge Gaseous 

Diffusion Plant Site Report indicate the primary contaminants incident to the recycled uranium are 

technetium-99 (99Tc), neptunium-237 (237Np), americium-241 (241Am), plutonium-238 (238Pu), and 

239/240Pu. 

The U:TRU activity ratios tended to run greater than 1,000:1 for samples containing significant 

contamination. There was an isolated instance in which the activity ratio of U:TRU was as low as 60:1 

on a relatively low-activity sample from Building K-25-W. However, the weighted average U:TRU 

activity ratio for all samples was greater than 1000:1 for every process building. This is a good 

indication that uranium is the dominant radiological contaminant in these areas. The weighted 

average distribution of TRU activity in samples from these buildings was approximately 16% 237Np, 

8% 241Am, 43% 238Pu, and 32% 239/240Pu.

However, the weighted average was strongly biased by one sample with the most activity from 

Building K-25-W. The weighted average of all other samples from all process buildings showed a 

TRU activity distribution of approximately 87% 237Np, 3% 241Am, 4% 238Pu, and 6% 239/240Pu. This 

distribution supports the process expectation that, of the TRU radionuclides, neptunium fluoride is 

likely to have been the most mobile in the gaseous phase and traveled farther (although generally 

only a short way) in the process before being deposited. The others are likely to have been present in 

the feed in lower concentrations and to have remained more readily in the heels of the feed cylinders.

Technetium is similar to uranium in its chemical nature, and forms compounds that carry through the 

chemical separation processes to a significant degree. A number of its compounds are gaseous 
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 8 of 14

under cascade conditions and, being of lower molecular weight than UF6, diffuse preferentially toward 

the enriched part of the cascade. These compounds were concentrated in the part of the equipment 

called the purge cascade. In this area, technetium was deposited in many items of equipment. 

During maintenance operations, some of these materials were spilled or released from the equipment 

(some in the gaseous state). This resulted in significant surface contamination in Units K-310-1, 

K-310-2, and K-310-3 of Building K-25 and Units K-402-1, K-402-8, and K-402-9 of Building K-27. In 

addition, an accidental release from a stripping system in Building K-29 resulted in significant 

technetium surface contamination of the cell floor. Characterization studies to date indicate that the 

observed activity ratio of U:Tc has been as low as 0.002:1 in these areas. Activity ratios less than 1:1 

for U:Tc are common in these areas, indicating that 99Tc contamination is significant.

2.2.1

September 1944 to August 1945

K-25 Processing History

Feed material (uranium hexafluoride) was first brought onsite in anticipation of startup of the 

cascades.

August 1945 to January 1946

The original cascade configuration was established in August 1945 when all stages of the K-25 

building came “on stream.” All feed that entered the cascade during this period was natural UF6. 

January 1946 to 1948

In early 1946, Building K-27 construction was completed, and its units were placed on stream as 

quickly as feasible. All feed that entered the cascade during this period was natural UF6.

1948 to 1951

The efficient production of 93% 235U required lengthening of the ORGDP enrichment cascade. This 

modification resulted in a significant change to the K-25/K-27 cascade configuration. All feed that 

entered the cascade during this period was natural UF6.

1951 to 1952

The third major processing building was K-29, which was east of Building K-27. All feed that entered 

the cascade during this period was natural UF6.

1952 to 1954

The Paducah Gaseous Diffusion Plant (PGDP) was brought on stream during this period. The overall 

optimum cascade configuration was an overlap between the PGDP and ORGDP sites. PGDP was 

used for the low-assay range of the enrichment process. Recycled uranium (RU) was first received at 

ORGDP in 1952 and was fed into the cascade in 1953.

1954 to 1957

Building K-33 came on stream as the ORGDP expansion continued. ORGDP processed a few 

reactor returns in 1955, and continued to receive product from PGDP for use as feed. 

1957 to 1959

The cascades (feed and withdrawal points) were modified during this period. ORGDP processed 

reactor returns in 1959, and continued to receive product from PGDP for use as feed. 

1959 to 1961

The ORGDP powerhouse was shut down and modifications of the cascade were made for efficiency. 

The remaining cascade configuration and feed and withdrawal points did not change. ORGDP 
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 9 of 14

processed reactor returns throughout this period, and continued to receive product from PGDP for use 

as feed. 

1962 to 1964

No cascade modifications occurred during this period, but ORGDP feed and tails withdrawal were 

modified. Feed and tails removal operations occurred in a single building. ORGDP processed reactor 

returns during this period, and continued to receive product from PGDP for use as feed. 

1964 to 1985

In 1964, Buildings K-25 and K-27 were shut down, with the exception of the K-25 purge cascade and 

its pigtail operation. In 1968, part of Building K-29 was shut down. The bottom of the cascade was 

now in Building K-31. ORGDP processed reactor returns through 1984, and continued to receive 

product from PGDP for use as feed. In June 1985, ORGDP was placed on standby; in 1987, the plant 

was shut down permanently. 

2.2.2

The K-25 area included support facilities that processed or stored radioactive materials. The 

identities, relative abundances, and chemical forms of radionuclides in the different work areas are 

presented in the characterization study for the transformation of K-25 to ETTP (MMES 1994). The 

following paragraphs summarize this study.

Facilities and Support Locations 

Uranium solubility class varied with process, but the residual RU radionuclides were typically as listed 

in Table 2-1. Radionuclides with more than one class listed tended to follow the uranium at the 

respective area (99Tc of class F followed uranium class F and M, while 99Tc of class M followed 

uranium of class M and S). The isotopes of curium are not discussed in the descriptions below, but 

were present at a lesser amount than the listed TRU. Thorium-230 was not measured at any location, 

but ingrowth from 234U should make 230Th marginally significant at some locations for intakes since 

about 1990. The radiological hazards by area are listed in Table 2-2 with the corresponding uranium 

solubility class.

Gaseous Diffusion Plant and Feed Materials Process Areas

The gaseous diffusion process included Cascade Buildings K-25, K-27, K-29, K-31, K-33, K-413, and 

K-631. The physical form of uranium in these areas was almost exclusively UF6 during the active 

years. During the inactive years, any residual UF6 has reacted with atmospheric moisture, forming the 

compound UO2F2, which is solubility Class F, but may have further reacted to Class M. No process 

history is indicative of appreciable Class S uranium compounds.

RU processing resulted in contaminants of 99Tc, 237Np, 241Am, 238Pu, and 239/240Pu. Significant amounts 

of other contaminants, such as beta/gamma-emitting fission products, were not revealed in the 

studies.

K-1131

K-1131 initially produced UF6 from virgin and recycled uranium oxides. It also produced the

compound UF4 as an intermediate step toward the final product. Later, the facility was used for feed 

vaporization and tails withdrawal.

The radionuclides in this area were the result of UF6 production and from the introduction of recycled 

uranium material. Isotopes present were 234U, 235U, 238U, 99Tc, 237Np, 241Am, 238Pu, and 239/240Pu. 

There were no significant amounts of beta/gamma-emitting fission products. Samples from this 

facility exhibited lower U:TRU activity ratios than those taken in most other areas. One sample 
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 10 of 14

produced a U:TRU activity ratio as low as 50:1. However, the facility-weighted average was 244:1. 

The composition of TRU material in this facility is consistent with the process expectation, showing a 

weighted average of approximately 60% 237Np, 12% 241Am, 22% 238Pu, and 7% 239/240Pu. The 

observed activity ratio of U:Tc has been as low as 30:1, which is an indication that uranium tends to 

dominate technetium in this area.

The process history of this area is consistent with that of lung solubility type Class F uranium 

compounds. Nothing about the fluorination process history suggests the presence of lung solubility 

type Class S uranium compounds to an appreciable extent.

K-1420 Decontamination Facility

The K-1420 Decontamination Facility initially supported decontamination, plating, and uranium 

recovery operations. It is still in use as a decontamination facility. The U.S. Department of Energy 

(DOE) used this facility to decontaminate equipment from K-25 and materials from other sites. The 

history of this facility suggests that Class F, M, and S uranium compounds could be present. Because 

the uranium recovery operation involved calcining procedures, Class F and Class S uranium 

compounds could have formed in this portion of the facility.

The isotopes found were 234U, 235U, 238U, 99Tc, 237Np, 241Am, 238Pu, and 239/240Pu. Significant amounts 

of beta/gamma-emitting fission products were not present. Samples from this facility exhibited lower 

U:TRU activity ratios than those from most other areas. Three samples showed U:TRU activity ratios 

less than 100:1, with one sample as low as 43:1. The composition of TRU material in this facility 

deviates from the K-25 Site average composition. Samples taken at this facility showed a weighted 

average of approximately 15% 237Np, 8% 241Am, 4% 238Pu, and 73% 239/240Pu. The high plutonium 

contribution could be the result of contamination from the cylinder wash area because plutonium 

tends to stay in the cylinder heels. The observed activity ratio of U:Tc has been as low as 0.5:1.

K-1410 Decontamination and Plating Facility

The K-1410 Decontamination and Plating Facility was used for various purposes, including storing 

clean trapping material, and dumping, cleaning, and refilling diffusion cascade traps; as a cleaning 

and decontamination facility before the construction of K-1420; and as an electroplating facility. 

Materials decontaminated at the K-1410 Facility include K-1131 Feed Plant equipment used to 

process Hanford reactor returns and S-50 Liquid Thermal Diffusion Process materials and equipment. 

In addition, records indicate that ash receivers from K-1131 were stored in and around K-1410. The 

process history indicates that the presence of Classes F, M, and S uranium is probable.

This area was not well characterized but the usual isotopes from natural and reactor return uranium 

occur.

K-1037 AVLIS Experiment Facility

The mission of this facility was to demonstrate the feasibility of the Atomic Vapor Laser Isotope 

Separation (AVLIS) 235U enrichment process on a production scale. This process, which is no longer 

active, used metallic uranium; therefore, the isotopes of concern are 234U, 235U, and 238U. No recycled 

uranium was processed at this facility and, therefore, significant TRU or 99Tc activity is unlikely. 

Contamination characterization studies to date have not revealed the presence of significant 

quantities of recycle-type contaminants. Process history dictates that uranium compounds in this area 

are Class S.

K-1015 Laundry Facility

This facility laundered anti-contamination clothing from K-25 and the Y-12 Plant. The isotopes 234U, 

235U, and 238U are of primary concern and of likely all solubility classes.
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 11 of 14

It is reasonable to expect the presence of radioactive materials other than uranium in this facility. 

However, recent characterization has not found RU radionuclides.

K-1066 Cylinder Yards

DOE stores UF6 cylinders in the K-1066 Cylinder Yards. Nondestructive measurements of “rust” from 

cylinders in the K-1066-B Cylinder Yard, performed by gamma spectroscopy, have shown an average 

uranium-to237Np activity ratio of 159:1. Analyses for 241Am and plutonium did not occur. Lower 

U:TRU activity ratios would be likely in recycle feed cylinders because much of the TRU material is 

likely to remain in the heel of the cylinder. Class F or M uranium compounds would be likely for this 

type of contamination.

K-1435 TSCA Incinerator

This is an active facility designed to dispose of toxic waste substances by high temperature 

incineration. Trace amounts of radioactive material are contained in the process stream. This facility 

receives wastes from Oak Ridge locations other than K-25 as well as from other DOE installations. 

The primary contaminants of interest are 234U, 235U, and 238U, although traces of other isotopes are 

present in the waste processed at this facility. Contamination characterization studies to date have 

not revealed the presence of any significant quantities of recycle-type contaminants. However, 

characterization is performed on the waste fed to the incinerator, which in turn can be used to 

characterize the isotopic composition of potential contamination. The Annual TSCA Incinerator 

Rolling Totals Report for 1995 shows a U:TRU activity ratio of 260:1 based on analysis for 237Np, 

238Pu, and 239Pu. However, if 228Th, 230Th, and 232Th are included with the TRU, a ratio of 65:1 is 

obtained. Therefore, this activity ratio will be assumed for this facility. The nature of the incineration 

process can reasonably be expected to concentrate radioactive contaminants in residue-handling 

equipment. It is possible that the incineration temperatures could convert relatively soluble 

compounds into relatively insoluble forms. Therefore, Class S uranium is presumed to exist in the 

residue-handling equipment. Areas and equipment where residues are not processed are presumed 

to contain Class F or MW uranium compounds.

K-1064, K-1417, K-1419

Waste drums containing sludge dredged from two settling ponds, K-1407 B and C, which received 

waste from the K-1420 operations, were stored near the K-1420 Facility. The Pond Waste 

Management Project (PWMP) has been involved in the fixation of this waste in cement. Facility K1064 is the PWMP Cement Truck Area; K-1417 is the PWMP Barrel Yard; and K- 1419 is the Sludge 

Fixation Facility. These areas have potential contamination from the K-1435 TSCA Incinerator. 

Analysis of this waste showed U:TRU activity ratios consistently less than 50:1. The weighted 

average U:TRU activity ratio was 16:1. The samples taken showed a weighted average of 

approximately 49.5% 237Np, 1% 238Pu, and 49.5% 239/240Pu. Analysis for 241Am was not performed. 

Since this waste was generated from operations at K-1420, it is reasonable to expect that uranium 

may exist in both Class M and S compounds.

Other Facilities

Other support buildings (including the K-1401 Maintenance Facility, the K-1231 Uranium Recovery 

Facility, and the K- 1004 and K-1006 Laboratory Facilities) generally contained less removable 

contamination. Isotopic activity ratios could not be accurately determined. However, the weighted 

average U:TRU activity ratio for samples taken from these areas was greater than 1,000:1. 

Therefore, all other areas of the ETTP are assumed to have an isotopic distribution similar to the main 

process buildings. However, operations at K-1004, K-1006, and K-1008-C are assessed to have the 

potential to produce contamination from Class S uranium in addition to Class F and M.
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 12 of 14

REFERENCES

BJC (Bechtel Jacobs Company) and Haselwood Enterprises, 2000, Recycled Uranium Mass Balance 

Project, Oak Ridge Gaseous Diffusion Plant (Currently Known as East Tennessee Technology 

Park) Site Report, BJC/OR-584, East Tennessee Technology Park, Oak Ridge, Tennessee, 

June. [SRDB Ref ID: 16497]

DOE (U.S. Department of Energy), 1997, Linking Legacies: Connecting the Cold War Nuclear 

Weapons Production Processes to Their Environmental Consequences, DOE/EM-0319, Office 

of Environmental Management, Washington, D.C., January. [SRDB Ref ID: 11930]

MMES (Martin Marietta Energy Systems), 1994, Assessment of Accessible Contamination at the K-25 

Site, Phase 3 Report: Cumulative Analytical Results, K/HS-570, K-25 Site, Oak Ridge, 

Tennessee, May 23. [SRDB Ref ID: 14229]

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

Implementation Guideline, OCAS-IG-001, Rev. 1, Office of Compensation Analysis and 

Support, Cincinnati, Ohio, August.

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, August.
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 13 of 14

GLOSSARY

anticontamination clothing

Outer clothing to prevent contamination of the skin and under clothing.

AVLIS

Atomic Vapor Laser Isotope Separation, a process for enriching 235U by ionizing uranium 

compounds in a vapor based on a laser tuned to the electronic structure of uranium 

compounds.

recycled uranium (RU)

Uranium that was irradiated in a reactor to produce plutonium. The uranium was chemically 

separated and purified, but contained minor amounts of TRU and fission products. 99Tc was 

the major fission product.

TSCA

Toxic Substances Control Act is a U.S. law that governs the disposal of toxic substances. 

Materials at K-25 that contain both radionuclides and toxic substances are burned in a TSCA 

compliant incinerator.
Document No.: ORAUT-TKBS-0009-2 Revision No.: 01 Effective Date: 10/04/2006 Page 14 of 14

Table 2-1. Solubility class of 

RU radionuclides. 

Isotope Solubility class

230Th M,S

238/239/240Pu M,S

237Np M

242/244Cm M

241Am M

99Tc F,M

Table 2-2. K-25 radiological hazards by area.

Site facilities

Uranium 

inhalation 

class

TRU 

present

99Tc 

present

Gaseous Diffusion Plant F,M Yes Yes

Feed Materials Processing Areas F,M Yes Yes

K-1131 F Yes Yes

K-1420 Decon Facility F,M,S Yes Yes

K-1410 Decon & Plating F,M,S Yes Yes

K-1064, K-1417, K-1419 M,S Yes Yes

K-1037 AVLIS S No No

K-1435 TSCA Incinerator F,M,S Yes Yes

K-1015 Laundry Facility F,M,S Yes Yes

K-1066 Cylinder Storage Yards F,M Yes Yes

K-1004, K-1006, K-1008C F,M,S Yes Yes