ORAU TEAM

Dose Reconstruction

Project for NIOSH

Oak Ridge Associated Universities I Dade Moeller I MJW Technical Services

Page 1 of 35

DOE Review Release 04/09/2013

Document Title:

Mound Site – Site Description

Document Number: ORAUT-TKBS-0016-2 

Revision: 01

Effective Date: 04/01/2013

Type of Document: TBD

Supersedes: Revision 00 PC-2

Subject Expert(s): Donald N. Stewart and Robert Leib

Approval: Signature on File Approval Date: 03/26/2013

Donald N. Stewart, Document Owner

Concurrence: Signature on File Concurrence Date: 03/26/2013

John M. Byrne, Objective 1 Manager

Concurrence: Signature on File Concurrence Date: 03/27/2013

Edward F. Maher, Objective 3 Manager

Concurrence: Vickie S. Short Signature on File for Concurrence Date: 03/26/2013

Kate Kimpan, Project Director

Approval: Signature on File Approval Date: 04/01/2013

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-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 2 of 35

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION 

NUMBER DESCRIPTION

03/30/2004 00 New Technical Basis Document for the Mound Site – Site Description. 

First approved issue. Initiated by Jeff Vollmer.

07/07/2006 00 PC-1 Page change revision initiated for biennial review. Incorporates NIOSH 

formal review comments. Changes were made to the required language 

on pages 5 and 6 in Section 2.0. No sections were deleted. Approved 

issue of Rev 00 PC-1. 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 J. Demopoulos. Approval:

Signature on File 06/06/2006

Stanley J. Waligora, TBD Team Leader

Signature on File 06/06/2006

John M. Byrne, Task 3 Manager

Signature on File 06/07/2006

Edward F. Maher, Task 5 Manager

Signature on File 06/06/2006

Kate Kimpan, Project Director

Signature on File 07/07/2006

James W. Neton, Associate Director for Science

03/13/2009 00 PC-2 Approved page change initiated to remove information pertaining to 

Monsanto Chemical Company, the subject of a class of employees 

added to the Special Exposure Cohort. These changes occurred on 

pages 6 - 13, 15, 16, 18, and 20 in Sections 2.0, 2.2, and 2.3, 

respectively. NIOSH required language was revised on page 5 in 

Section 2.0. Updated references on pages 29 - 30 in Reference 

Section. In this revision, Figure 2-1 was formerly Figure 2-3. Figures 2-

1 and 2-2 from the previous revision were deleted. Incorporates formal 

internal and NIOSH review comments. No Sections were deleted. 

Training required: As determined by the Task Manager. Initiated by 

Donald N. Stewart. Approval:

Signature on File 03/02/2009

Donald N. Stewart, Document Owner

Signature on File 03/03/2009

John M. Byrne, Task 3 Manager

Signature on File 03/02/2009

Edward F. Maher, Task 5 Manager

Signature on File 03/11/2009

Kate Kimpan, Project Director

Signature on File 03/13/2009

James W. Neton, Associate Director for Science
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 3 of 35

04/01/2013 01 Revision initiated to incorporate SEC-00090, SEC-00171, and SEC00207. Updated Table 2-1 with information for 2003 and 2010. Added 

Special Exposure Cohort information pertaining to the SW Building in 

Section 2.1.3. Incorporates formal internal and NIOSH review 

comments. Training required: As determined by the Objective 

Manager. Initiated by Donald N. Stewart.
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 4 of 35

TABLE OF CONTENTS

SECTION TITLE PAGE

Acronyms and Abbreviations ............................................................................................................... 5

2.1 Introduction .............................................................................................................................. 7

2.1.1 Purpose........................................................................................................................ 8

2.1.2 Scope........................................................................................................................... 8

2.1.3 Special Exposure Cohort Petition Information for the Mound Plant............................... 8

2.2 Site Activities and Processes ................................................................................................... 9

2.2.1 Mound Laboratory ........................................................................................................ 9

2.2.2 Buildings with Radionuclide Activity............................................................................ 12

2.3 Attributions and Annotations .................................................................................................. 31

References ........................................................................................................................................ 32

Glossary ............................................................................................................................................ 34

LIST OF TABLES

TABLE TITLE PAGE

2-1 Chronology of significant Mound Laboratory programs and events ........................................ 10

2-2 Radionuclides and related compounds for HH Building.......................................................... 13

2-3 Radionuclides and related compounds for Building PP (38)................................................... 14

2-4 Radionuclides and related compounds for R Building ............................................................ 15

2-5 Radionuclides and related compounds for SM Building.......................................................... 17

2-6 Cotter Concentrate composition............................................................................................. 18

2-7 Radionuclides and related compounds for SW Building ......................................................... 19

2-8 Radionuclides and related compounds for T Building............................................................. 20

2-9 Radionuclides and related compounds for WD and WDA Buildings ....................................... 23

LIST OF FIGURES

FIGURE TITLE PAGE

2-1 Mound (Unit V) site map......................................................................................................... 13
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ACRONYMS AND ABBREVIATIONS 

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act

CFR Code of Federal Regulations

Ci curie

CWPF Consolidated Waste Processing Facility

D deuterium

D&D decontamination and demolition

DOE U.S. Department of Energy

DOL U.S. Department of Labor

EDTA ethylene diamine tetraacetic acid

EEOICPA Energy Employees Occupational Illness Compensation Program Act of 2000

ft foot

g gram

gal gallon

HTO tritium oxide (water or water vapor)

kg kilogram

lb pound

LLW low-level waste

LSA low specific activity

mg milligram

NIOSH National Institute for Occupational Safety and Health

ORAU Oak Ridge Associated Universities

pCi picocurie

POC probability of causation

ppm parts per million

PUREX plutonium-uranium extraction

R&D research and development

RTG radioisotopic thermoelectric generator

SEC Special Exposure Cohort

sOBT physiologically soluble organically bound tritium

SRDB Ref ID Site Research Database Reference Identification (number)

SRS Savannah River Site

t ton

T tritium

TBD technical basis document

TRU transuranic

U.S.C. United States Code

yd yard
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 6 of 35

§ section or sections
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 7 of 35

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 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

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

reasons

 

1 The U.S. Department of Labor (DOL) is ultimately responsible under the EEOICPA for determining the POC.
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 8 of 35

2.1.1 Purpose

The purpose of this technical basis document (TBD) is to provide a site description for the Mound 

Laboratory that contains technical basis information for use by the Oak Ridge Associated Universities 

(ORAU) Team to evaluate the total occupational dose for EEOICPA claimants.

2.1.2 Scope

The Mound Laboratory played an important role in the U.S. nuclear weapons program. Mound 

Laboratory activities were originally established in Dayton, Ohio, in the summer of 1943. The 

Monsanto Chemical Company operated the Dayton Laboratory at Units I, II, III, and IV. Of these, 

Units III and IV were created to produce large quantities of polonium. Operational experience at Units 

III and IV demonstrated the need for a specialized facility for polonium production and associated 

activities. This need led to the design and construction of the Mound Laboratory, initially known as 

Unit V of the Dayton Laboratory. The Mound Laboratory was initially occupied in 1948, and various 

research programs were begun; polonium production work was transferred to the new facility in 1949. 

The site’s role grew to include nuclear weapons component development and production, and such 

secondary missions as radioactive waste management and recovery, the use of radioactive materials 

for nonweapons purposes, and the purification of nonradioactive isotopes for scientific and 

commercial research. This TBD contains supporting documentation to assist in the evaluation of 

worker dose from these processes at the Mound Laboratory, using the methodology in NIOSH 

implementation guides (NIOSH 2002, 2007).

Consideration of potential exposures and dose reconstruction methods for Monsanto Chemical 

Company operations are outside the scope of the Mound Laboratory TBDs. 

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

of Mound operations. An objective of this TBD is to provide supporting technical data to evaluate, 

with favorable to claimant assumptions, the total Mound occupational dose that can be associated 

reasonably with worker radiation exposure covered under EEOICPA legislation. This dose includes 

occupational internal and external exposures, occupationally required diagnostic X-ray examinations, 

and onsite exposure to site environmental releases. This TBD addresses evaluation of unmonitored 

and monitored worker exposure and missed dose. Consistent with NIOSH (2002, 2007), this 

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

methods and protection factors.

In addition, this TBD presents technical basis methods used to prepare the Mound worker dose 

records for input to the NIOSH Interactive RadioEpidemiological Program and the Integrated Modules 

for Bioassay Analysis computer programs used to evaluate worker dose. Because information on 

measurement uncertainties is an integral component of the NIOSH approach, this document 

describes the uncertainty evaluation for the Mound exposure and dose records.

Section 2.2 describes Mound facilities and processes as well as historical information related to 

worker internal and external exposures. 

2.1.3 Special Exposure Cohort Petition Information for the Mound Plant

Classes Added to the SEC

Employees of the Department of Energy (DOE), its predecessor agencies, and DOE 

contractors or subcontractors who worked in any areas at the Mound Plant site from 

October 1, 1949, through February 28, 1959, for a number of work days aggregating at 

least 250 work days or in combination with work days within the parameters 
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 9 of 35

established for one or more other classes of employees in the SEC (SEC-0090; Leavitt 

2008).

All employees of the Department of Energy (DOE), its predecessor agencies, and its

contractors and subcontractors who had at least one tritium bioassay sample and 

worked at the Mound Plant in Miamisburg, Ohio from March 1, 1959 through March 5, 

1980, 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 (SEC-00171; Sebelius 2010).

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

contractors and subcontractors who worked at the Mound Plant in Miamisburg, Ohio, 

from September 1, 1972 through December 31, 1972, or from January 1, 1975 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 included in the 

Special Exposure Cohort (SEC-00207; Sebelius 2012).

Dose reconstruction guidance in this document for periods before March 6, 1980, is presented to 

provide a technical basis for partial dose reconstructions for claims not covered in the SEC class 

through March 5, 1980. Although NIOSH found that it is not possible to completely reconstruct 

radiation doses for the SEC classes above, 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 

employees who worked in any areas of the Mound Plant during the periods from October 1, 1949 

through February 28, 1959, or September 1, 1972 through December 31, 1972, or January 1, 1975 

through December 31, 1976; or who worked in R or SW Buildings (as indicated by tritium bioassay)

during the period from March 1, 1959 through March 5, 1980, but who do not qualify for inclusion in 

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

2.2 SITE ACTIVITIES AND PROCESSES

2.2.1 Mound Laboratory

The Mound Laboratory facility was established on a hill 878 feet above sea level and about 200 ft 

above the Miami River in Miamisburg, Ohio. Mound Laboratory became the first permanent U.S. 

Atomic Energy Commission facility in May 1948. At the Mound Laboratory there were originally 14 

buildings with 360,000 ft2 of space. Polonium processing began in February 1949 (Gilbert 1969). 

During the early years of operation at the Mound Laboratory in Miamisburg, a number of small 

research activities were carried out involving 226Ra, 227Ac, 228Th, 232Th, 230Th, 231Pa, and 233U (Meyer 

1992). From the early 1950s to the early 1980s Mound conducted various programs that involved 

extraction and purification of 226Ra, 227Ac, 230Th, and 231Pa. Ores were typically depleted of uranium 

before processing.

The narrowly focused polonium production work expanded to the development and production of 

weapons components. Production of 238Pu and 239Pu grew from the early work with polonium (Gilbert 

1969). Mound’s main focus was to support DOE weapons and nonweapons programs, especially in 

the areas of chemical explosives and nuclear technology. Its principal mission was to research, 

develop, and manufacture nonnuclear explosive components for nuclear weapons that were 

assembled at other sites.
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Early programs investigated chemical and metallurgical properties of 210Po and its applications. 

Research and development (R&D) included the fabrication of neutron and alpha sources for weapons 

and nonweapons use. Starting in the early 1950s, Mound developed radioisotopic thermoelectric 

generators (RTGs), which have been used on a variety of missions to provide heat and power for 

spacecraft. Production of 210Po declined in the 1960s until it phased out in 1971 (Meyer 1992). 

Developing, producing, and providing surveillance of detonators for military applications began in 

1957. Explosive timers were developed in 1959, and manufacture of the timers began in 1963

(MEMP 2000). Ferroelectric transducers and firing set component development and manufacture 

began in 1962 (MEMP 2000). 

Tritium handling technologies began in the mid-1950s. Mound tritium programs supported weapons 

and nonweapons programs (MEMP 2000). Beds and vessels containing uranium and/or other metals 

were used to trap and store tritium in the form of a metal tritide. In addition, research was conducted 

on metal tritides and tritium targets might also have been processed.

Other major operations included:

• Manufacture of enriched stable isotopes for medical, industrial, and general research; 

• Development and manufacture of chemical heat sources; 

• Recovery and purification of tritium from waste from Mound and other DOE sites; 

• Development of radioisotopic heat sources for the National Aeronautics and Space 

Administration and other programs; 

• R&D of chemical explosives and pyrotechnics, adhesives, plastics, and elastomers for the 

nuclear weapons program; 

• R&D of thermonuclear energy fuel systems; 

• R&D of the joining of exotic metals; 

• Development of instrumentation for the nuclear safeguard program; 

• R&D of separation of gases and energy conversion systems; and

• R&D of technologies for radioactive waste management. 

Table 2-1 summarizes Mound operations.

Table 2-1. Chronology of significant Mound Laboratory programs and events.

a

Year Activity

1946 Mound Laboratory planning started.

1948 Mound Laboratory occupied (May).

1949 Polonium operations moved from Dayton Units to Mound Laboratory beginning in February.

First program separated Ra-226 from barium-rich uranium ore, pitchblende residue called K-65, 

which consisted of the following:

Constituent Percent by weight

Water 30%

Lead oxide 19%
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Year Activity

Barium sulfate 7% (375 mg of radium in the barium)

Silicon dioxide 35%

Metals 9% trace metals similar to Cotter Concentrate

Experimental extraction of Ra-226 from the K-65 was conducted in the R Building. In October 

Mound received 200 lb of K-65 in a single drum.

Study of processes for decontamination of radioactive waste from plutonium, production reactors 

at Hanford.

From 1948 to 1952 three different types of processing wastes were studied to concentrate 

constituents such as Cs-137, Ru-106, SR-90, Zr-93, Co-60, Nb-94, Sb-125, Te-123, Ni-63, rareearth elements, and Pu-239. Bench scale testing began in R Building. 

1950 Separation of Po-208 and Po-209 from proton (accelerator) irradiation of bismuth.

Separation of Ac-227 from irradiated Ra-226.

Uranyl sulfate – heavy water fuel system research.

Civilian power reactor research involving uranium, Pa-231, and Pu-239; mission ended in 1963.

1951 Small amount of research with Ra-226 in preparation of cave operation in SW Building. Involved 

irradiated Ra-226 and recovery of Ac-227 and Th-228 from Ra-226.

1952 Pilot plant installed in SW Building for processing reactor waste. Reactor waste processing 

areas also included Warehouses 9 and 13 and WD, SD, SW, R, and M Buildings.

1953 SW Building for tritium handling constructed with a dirt floor.

1954 Invention of the Po-210-fueled RTG.

Initiation of several programs requiring tritium-handling technologies.

Construction of thorium refinery for breeder reactor program (never operated).

1955 Repackaging of 6,000 55-gal drums containing thorium ore and sludge occurred through 1965 at 

three different times to help prevent the possibility of further contamination.

August: Small research program in R Building involving recovery and subsequent purification of 

Pa-231 from natural sources.

June: Radium Cave operation shut down (Ra-226, Ac-227, Th-228, Ra-223, Ra-224 progeny)

1956 Completed separation of 1.3 g of Pa-231 in HH (Hydrolysis House) Building.

Weighable quantities of Th-230 (ionium) separated.

Pu-239-Be neutron sources manufactured.

Nuclear weapon detonator development, production, and surveillance; mission ended in 1989.

1959 Pu-239 reactor fuels laboratory operational.

Tritium waste recovery and purification facility operational.

U-233 research involving about 10 research personnel.

1960 Pu-238 used in large quantities in production operations. Process areas included the R, SM

(Special Metallurgical), and PP (Plutonium Processing) Buildings.

1961 Development of Pu-238 heat sources for thermoelectric generators.

1963 Several Po and gadolinium polinide heat sources containing 100–1,000 Ci of Po-210 were 

encapsulated in refractory metal.

1964 190 mg of Ac-227 was processed in the New Cave area.

1965 Gaseous effluent control system operational in SW Building.

1966 Thorium ore and sludge moved to bulk storage in Building 21.

1967 54,000 Ci of high-purity Po-210 were processed for Mound experimental work and commercial 

use.

14.5 kg of Pu-238 were recovered from waste material.

1968 PP Building 38 operational for processing Pu-238.

1969 Waste line break and subsequent contamination of the abandoned Miami-Erie Canal bed with 

Pu-238. 

Began tritium recycling from retired weapon parts.

3,701 Ci of Po-210 were produced for both internal and external customers.

Six Systems for Nuclear Auxiliary Power (SNAP)-27 sources were produced. Each source 

contained 3,735 Ci of Pu-238.

10/1970–

06/1971

Plutonium inventory was reduced to a minimum level. 22.5 kg of Pu-238 scrap was shipped to 

the Savannah River Site (SRS) for burial.

1972 Tritium effluent control project began.

Nonweapons polonium work terminated.
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Year Activity

1973 Pu-238 oxide was processed for 4 multihundred watt (4.2 kg each) and 2 Viking sources (1.2 kg 

each)

1974 Thorium ore and sludge completely removed from site.

Po-210 decontamination of Technical (T) Building completed.

1975 Pu-238 recovery operations terminated.

1977 Californium Multiplier Neutron Radiography Facility installed.

1989 Removal of soil contaminated with uranium near Building 34.

1990 Pu-238 decontamination of inactive laboratories in R Building.

1991 Removal of Pu-238-contaminated waste line connecting HH Building with WD Building.

1993 DOE decision to transfer defense mission from Mound.

Pu-238 decontamination of PP Building 38 and Acid Leach Field (Area D).

1994 Demolition of SM Building structure contaminated with Pu-238.

1995 All weapon components production terminated.

1996 Demolition of SD Building (sanitary waste treatment facility) and Building 21 (thorium ore and 

sludge bulk storage facility) including excavation of contaminated soil.

Miami-Erie Canal removal action (Pu-238 contaminated sediments) fieldwork begins in October.

1997 Removal of soil contaminated with Ac-227 at Area 7.

1998 Miami-Erie Canal removal action fieldwork completed; approximately 30,000 yd3 removed for 

offsite disposal.

2003 All operations ceased.

2010 Remediation activities completed (DOE 2011).

a. Adapted from DOE 1993, DOE 1999, DOE 2011 and EPA 2003.

2.2.2 Buildings with Radionuclide Activity

The information in this section is from EG&G (1995) unless otherwise noted.

Figure 2-1 shows the Mound Laboratory site. The buildings of concern at the Mound Laboratory 

include HH, PP (also called Building 38), R, SM, SW, T, and WD/WDA. Supporting buildings that 

were not directly involved in research or production operations that are considered in this TBD 

evaluation include:

• Warehouses 9, 13, and 15; and

• Buildings 15, 21, 34, 50, 59, 68, B, E, H, I, M, P, RR, and SD. 

HH Building

HH Building or Hydrolysis House derived its name from its primary function: the hydrolysis of highly 

radioactive bismuth chloride and aluminum chloride solutions. In 1963, the HH Building was 

converted to stable gaseous isotope separation using thermal diffusion, liquid diffusion, and cryogenic 

processes. Table 2-2 is a summary of the rooms, dates, and radionuclides for the HH Building. All 

dates represent the duration of actual use of radioisotopes in the projects.

PP Building (38)

The Plutonium Processing (PP) Building (38) was completed in December 1967. SM Building 

processes, fabrication operations, and recovery processes were transferred to PP Building along with 

waste treatment facilities, R&D including material research, and analytical laboratory support 

activities. PP Building was used primarily for processing 238Pu dioxide from the Savannah River Site 

(SRS).

Plutonium dioxide was received in a powder form with the following isotopic mixture and a purity of 

99.9% according to (EG&G 1995).

(1 ppm) – 1E-4% Pu-236 3.0% Pu-240

80.2% Pu-238 0.6% Pu-241
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15.9% Pu-239 0.1% Pu-242

Figure 2-1. Mound (Unit V) site map. 

Table 2-2. Radionuclides and related compounds for HH Building. 

Rooms Radionuclides and related compounds Dates used

HH-3, 4 H-3 1960–1990

Xe (all isotopes) 1964–1983

Stable isotopes, Kr-85 1964–present

HH-5 Pa-231, Fe-59, Al-26, Ca-45, Co-60, Cu-65 1955–1956

U-233, -234, -235, -238, Th-230, -232, Pa-231, Th-230, -232 

progeny

1956

H-3 1960–1990

Xe (all isotopes) 1964–1983

Stable isotopes, Kr-85 1964–present

HH-6 Pa-231, Fe-59, Al-26, Ca-45, Co-60, Cu-65 1955–1956

U-233, -234, -235, -238, Th-230, -232, Th-230, -232 progeny 1956

HH-8 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-209, -210, Po(NO3)2, 

Fe-55, -59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, 

V-52, Te-121 to -134, Hg-203

1949–1958

Kr-85, Xe (all radioisotopes) 1961–1963

HH-9 H-3 1965–1985

HH-10 to 12 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-209, -210, Po(NO3)2, 

Fe-55, -59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, 

V-52, Te-121 to 134, Hg-203

1949–1958

HH-119 to 122 H-3 1964–1980
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Reference to 238Pu in PP Building was a composite of the mixture identified above. This mixture 

included trace amounts of 241Am, 237Np, and 234U. Dates represent the duration of radioisotope use in 

the projects.

Thorium-232 was often substituted for 238Pu compounds for modeling purposes in R&D, because this 

isotope was less expensive and less hazardous, and had physical characteristics similar to 238Pu. It is 

possible, therefore, to find 232Th compounds identical to the 238Pu compounds.

The term “high-fired,” which is sometimes used, implies that the plutonium compound has been 

heated in a plasma torch process such that the lung solubility type is definitely S. The term “non-highfired” implies an absence of such heating and, in extreme cases where indicated, a lung solubility type 

of M or even F might exist where there is high solubility.

Table 2-3 summarizes PP Building rooms, dates, and radioisotopes.

Table 2-3. Radionuclides and related compounds for Building PP (38). 

Room Radionuclides and related compoundsa Dates used

PP-CORR-5A PuO2 1967–1974

PP-6 PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4 1967–1980

PP-6W PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4 1967–present

PP-CORR-10 PuO2 1967–present

PP-13, 14 PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4 1967–1980

PP-CORR-15 to 17 PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4 1967 –1974

PP-18 PuO2, Pu(NO3)4 1967–present

PP-24 PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4 1967–present

PP-100 PuO2 1967–present

PP-113 Pu-(238,239)O2

Varied orphaned sources

1957–1989

1988–present

PP-CORR-115 Pu-(238,239)O2 1967–present

PP-127 PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4 1967–present

PP-CORR-134 to 136 PuO2 1967–present

PP-CORR-140 to 142 PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4, Th-232, ThO2, Th(NO3)4, 

Th(C2O4)4, Th(OH)4

1967–present

PP-143(A1) PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4, Th-232, ThO2, Th(NO3)4, 

Th(C2O4)4, Th(OH)4

1967–1980

PP-142(A2) PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4, PuF4, PuC, Th-232, ThO2, 

Th(NO3)4, Th(C2O4)4, Th(OH)4, ThF4

1967–1980

PP-145(A3) PuO2 1967–1982

PP-146(B1) PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4, PuF4, PuC 1967–1980

PP-147(B2), PP-148(B3) PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4, PuF4, PuC, Th-232, ThO2, 

Th(NO3)4, Th(C2O4)4, Th(OH)4, ThF4

1967–1980

PP-149(B4) PuO2 1967–1982

PP-150 to 156 (C1 to C3, 

D1 to D3)

PuO2, Pu(NO3)4, Pu(C2O4)4, Pu(OH)4, PuF4, PuC 1967–1980

PP-157(E1), 158(E2), 162,

163

PuO2 1967–1980

PP-159(E3) PuO2, Pu(NO3)4, Pu(OH)4, PuF4 1967–1980

a. Plutonium-238 was the designated radioisotope in every room unless otherwise specified. Other isotopes of the mixture 

identified in the introduction along with small amounts of 241Am, 237Np, and 234U. Thorium-232 was sometimes used as 

a stand-in for plutonium.

R Building

R (for Research) Building, which was built in 1948, has handled a number of programs involving a 

number of radionuclides over the years. Some of the major programs are discussed below, as are 

elemental radionuclides and radioisotopic compounds from those processes.
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Beginning in the fall of 1948, R&D for the 210Po program began. This was pilot-scale work for 

processing in T Building. R&D work with polonium extended into the 1970s.

Plutonium-238 research began in R Building in1959 and continued through the 1960s. The plutonium 

isotope concentration was the same as referenced in EG&G (1995) for the material Mound received 

from SRS. 

R&D was conducted with tritium in the R Building. Experimentation with metal tritides and deuterides 

such as uranium tritide and lithium tritide occurred, as did developmental studies with tritiated water.

Some tritides and tritiated compounds were so poorly metabolized that their biological half-lives were 

on the order of hours. This was not true for uranium tritides.

Table 2-4 summarizes rooms, dates, and radioisotopes in R Building.

Table 2-4. Radionuclides and related compounds for R Building. 

Rooms Radionuclides and related compoundsa Dates used

R-117, 120, 127 to 131, 

133, 143, 144, 151, 

152, 155, 159, 160 to 

162, 167

AlCl3, BiCl4, Ag-Po, Te-Po, PoCl2, Po-210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1948–1951

R-105, 106 H-3, HTO 1958–1965

H-3, Li(D,T), U-238(D,T) 1965–1978

R-108 Po-208, -210, H-3, 1948–1965

H-3, Li(D,T), U-238(D,T), Ti(D,T), other tritides (Type F, S) 1975–present

R-110 Po-208, -210 1955–1972

H-3 1972–present

R-111 Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-223, -224, -226, Th-228, 

-229, -239, Ac and Ra progeny Po-208, -210, H-3

1951–1965

R-112 H-3, Li(D,T), U-238(D,T), other tritides (Type F, S) 1973–1993

R-113 to 115 Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-223, -224, -226, Th-228, 

-229, -239, Ac and Ra progeny

1951–1955

Po-210, Pu-238, -239, Po/Be, PoF2, Po/B, Pu/Be, PuF2, Pu/B 1956–1961

H-3 1978–present

R-116 Po-210, Pu-238, -239, Po/Be, PoF2, Po/B, Pu/Be, PuF2, Pu/B 1956–1961

Pu-238, -239, PuBe, Am-241 1956–1962

H-3, Li(D,T), U-238(D,T) 1960–1965

R-117 Pu-238, -239, Pu/Be, PuO2, Pu-238/Zr, Pa-231, Po-210/Be, Th-230 1948–1990

R-118 Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-223, -224, -226, Th-228, 

-229, -230, (Ac and Ra progeny)

1955

U-234, -235, -238, Pa-231, Th-230, -232, and Th-232 progeny 1956–1958

R-119 to 121,123 Po-210, Bi-210, AlCl3, BiCl3, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-226, Th-228, -229, -230, 

AcF4, AcI4, Ac-227 progeny, 

1951–1953

Pa-231, Th-230, -232, and Th-232 progeny, U-234, -235, -238 1956–1958

Pu-239, Am-241 1956–1962

Pu-238, oxide, neutrons 1959–1962

Pu-238, Pu(NO3)4, Pu(NO3)6, PuO2, Pu-Cu, Pu(C2O4)4, 

Pu(O2).5H2O, Pu(OH), PuF4, PuCl4, Pu-Se, Pu-Zr, H-3, Pu rare 

earths, Po alloys and compounds

1959–1979

R-127 Po-210, Bi-210, AlCl3, BiCl3, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

Fe-55, -59 1952–1954

H-3 1956–1961

PuO2, PuF4, Pu-MoCl4, Pu-MoF4 1965–1978

H-3, Pu-239 1987–present
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Rooms Radionuclides and related compoundsa Dates used

R-128 Po-210, Bi-210, Po(NO3)4, PoCl2, Po/Ag, Po/Te 1948–1954

PuO2, PuF4, Pu-MoCl4, Pu-MoF4 1965–1978

H-3, U(D,T) 1987–present

R-129,130 Po-210, Bi-210, P(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-223, -224, -226, Th-228, 

-229, -230

1951–1953

Pu-238, PuO2, PuF4, Pu-MoCl4, Pu-MoF4, PuCl4 (Th-232 

compounds replacing Pu-238 compounds for analytical studies)

1965–1978

H-3, Pu rare earths, Po alloys and compounds 1990–present

R-131 Po-210, Bi-210, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

Pu-238, PuO2, PuF4, Pu-MoCl4, Pu-MoF4, PuCl4, Cm-244 1965–1978

R-133 Po-210, Bi-210, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1954

Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-226, Th-228, -229, -230, 

AcF4, AcI4, Ac-227 progeny

1951–1953

Pa-231, U-234, -235, -238, Th-230, -232; also Th-230, -232 progeny 1956–1958

Pu-238, PuO2, PuF4, Pu-MoCl4, Pu-MoF4, PuCl4, Cm-244 1965–1978

R-134 H-2, U-238, U-238(D,T) 1986–present

R-137 Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-226, Th-228, -229, -230, 

AcF4, AcI4, Ac-227 progeny

1951–1953

R-140 Th-228, -230, -232, U-234, -235, -238, Pu-238, -239, Po-208, -209, 

-210, Cs-137, Pa-231, Ac-227, Ra-223, -224, -226, Sr-90

1950–1969

Pu-238, -239, -240, -241 (alloys, compounds, and mixtures), 

Pu(NO3)2, Ac-227, Am-241

1969–present

R-142 Ra-226, Ra(CO3), Ra(NO3)2, RaBr2, Ac-227, Ac(C2O4)4, AcF2, K-40, 

Ba(NO3)2, Th-228, -229, -230, radon and progeny, Po-208, -209, 

-210 

1949–1953

Pu-238,239, U-234,235,238, Th-230, Pa-231, Th-230 progeny 1956–1969

PuO2, (for Pu-238,239) 1966–1979

R-143,144 Po-210, Bi-210, AlCl3, BiCl3, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

PuO2, (for Pu-238, -239) 1972–1976

R-145,147 Ra-226, Ra(CO3), Ba(CO3), Ac(NO3)2, Ra/Ba, Ac-227, Ac(C2O4)4, 

AcO2, Th-228, -229, -230

1949–1954

Fe-59, Al-26, Ca-45, Co-60, Pa-231, Cu-65 1955–1956

Pu-239, Am-241 1956–1959

Pu-238 oxide, neutrons 1960–1962

Pu-238, -239, PuO2, U-234, -235, -238 1968–1975

R-148,149 Ra-226, Ra(CO3), Ba(CO3), Ac(NO3)2, Ra/Ba, Ac-227, Ac(C2O4)4, 

AcO2, Th-228, -229, -230, Po-208, Pa-231

1949–1954

Fe-59, Al-26, Ca-45, Co-60, Pa-231, Cu-65, Pu-238 1954–1958

Pu-238, Pu(C2O4)4, Pu(NO3)4, Th-230, 1960–1968

PuO2, Pm-146 to -149, U(234)(NO3)4, U(234)O2, Pu/Zr 1970–1980

R-151 Po-210, Bi-210, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

Pu-238, -239, Pu(NO3)4, Pu(NO3)6, PuO2, Pu(OH), Pu(C2O4)4, 

Pu(O2).5H2O, PuCl4, PuF4, Pu(SO4)2, Np-237, and EDTA, citrates, 

and other substances acting like chelating agents were present

1958–1983

R-152 Po-210, Bi-210, AlCl3, BiCl3, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1954

Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-226, Th-228,229,230, AcF4, 

AcI4

1951–1953

R-155 Po-210, Bi-210, AlCl3, BiCl3, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

U-235, -238, Pu-239, Np-237, Cm-244, Am-241, (the following were 

tried in combination with those listed: Ni-63, Co-60, Si-31, Z-65, 

Bi-210, Pb-210, Zr-95, Al-26 are rare-earth elements)

1956–1969

R-159 Po-210, Bi-210, AlCl3, BiCl+, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951
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Rooms Radionuclides and related compoundsa Dates used

U-235, -238, Pu-239, Np-237, Cm-244, Am-241, (the following were 

tried in combination with those listed: Ni-63, Co-60, Si-31, Z-65, 

Bi-210, Pb-210, Zr-95, Al-26 are rare-earth elements)

1956–1969

R-160,161 Po-210, Bi-210, AlCl3, BiCl3, Po(NO3)2, PoCl2, Po/Ag, Po/Te 1948–1951

Ac-227, AcO2, Ac(NO3)4, Ac(C2O4)4, Ra-226, Th-228, -229, -230 1951–1953

R-162 Ru-106, Cs-137, Sb-125, Te-121,127, Zr-93,95, Nb-94, Sr-90, 

Pu-238, -239, Y-88, -90, -91, Ce-144 and other rare earths

1948–1951

Pu-238, -239 1950

U-233, -235, -238 1958–1959

R-166 Po-210 1961–1968

R-167 Ru-106, Cs-137, Sb-125, Te-121 to -134, Zr-93, -95, Nb-94, Sr-90, 

Pu-238, -239, Y-88, -90, -91, Ce-144 and other rare earths

1948–1951

Pu-239, U-234, -235, -238, I-131, Cs-137, Ce-144, Sr-90, Tc-99, 

Xe-133, Y-88, -90, -91

1949–1952

Fe-55, -59, Al-26, Ca-45, Co-60, Pa-231, Cu-65 1954–1955

Pu-239, Ac-227, neutrons 1955–1957

U-233, Th-229, -230, -232 1958

Sr-90, Y-88, -90, -91, Pa-231 1960–1962

Pa-231, -233, Ce-141, -144, Am-241, Cm-244, U-233, Th-230, -232, 

Ra-226, Ti-208

1956–1987

R-168 U-238, UF4, UO2 1958

R-169 Th-230, -232, U-234, -235, -238, Pu-238, -239, Po-208, -209, -210, 

Cs-137, Pa-231, Ac-227, Ra-223, -224, -226

1960–1980

U-235, -238, Pm-147, Ca-45 1980–present

R-170 U-238, Ca-45 1960–1964

R-171,172 Ra-223, -224, -226, Ac(NO3)2, Ac-227, Ac(C2O4)4, AcO2, Th-228, 

-229, -230, Ac and Ra progeny

1949–1954

U-235, -238 1961–1963

Pu-238, -239, -240, -241 (compounds, alloys and mixtures), 

Am-241, Ac-227, Ra-226

1965–1991

R-175,176 H-3 1970–present

R-197A Pu-238, -239, PuO2, Cm-244 1970–present

R-198 Pu-238, -239, Pu(NO3)4, PuO2, PuF4, Np-237, Ac-227, Cm-244, H-3, 

Po-210, PoF4, Li(D,T), U-234, -235, -238, U(D,T), Am-241, Pr-146 to 

-149

1956–1982

R Building crawl space Pu-238, -239, Ra-226, Ac-227, Po-210, Th-228, -229, -230 1948–present

R-CORR-5 Ac-227 1948–1984

a. D = deuterium; EDTA = ethylene diamine tetraacetic acid; HTO = tritium oxide (water or water vapor); T = tritium.

SM Building

The Special Metallurgical (SM) Building was built in 1960 and became operational in 1961. It was 

designed for the reception of a liquid plutonium nitrate mixture from SRS that was used in a variety of 

programs, mainly heat source projects. In addition, SM Building housed recovery processing, waste 

treatment facilities, R&D, and analytical support activities. Table 2-5 summarizes SM Building rooms, 

dates, and radioisotopes.

Table 2-5. Radionuclides and related compounds for SM Building. 

Room Radionuclides and related compounds Dates used

SM-1 Pu(NO3)4, PuO2, Pu(C2O4)4, Pu(OH)4, PuF4 1961–1962

Pu(NO3)4.5H2O, Pu(NO3)6, PuO2.XH2O, PuO2, Pu(C2O4)4, 

PuO2.5H2O, Pu(OH), Th(NO3)4, ThO2, Th(OH)4, ThO2.XH2O

1962–1967

SM-2 PuO2 1961–1967

SM-3,10 Pu(NO3)4, PuO2, Pu(C2O4)4, Pu-238, neutrons 1961–1967

SM-20 Sealed sources 1961–1967

SM-21 PuO2, Th-232 oxide (EDTA and citrates acted like chelating agents) 1961–1967
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Room Radionuclides and related compounds Dates used

SM-26 Pu(NO3)4, PuO2, Pu(C2O4)4, Pu(OH)4, PuF4 1961–1967

SM-27,28 Pu(NO3)4.5H2O, Pu(NO3)6, PuO2, Pu(C2O4)4, PuO2.5H2O, Pu(OH), 

PuF4, PuCl4

1961–1965

Pu(NO3)4, Pu(NO3)4.5H2O, PuO2, PuO2.X H2O, Pu(C2O4)4, Pu(OH) 1965–1967

SM-34 Pu(NO3)4.5H2O, PuO2, Pu(SO4)2, PuF4, Am(NO3)4, AmO2,

Am(SO4)2, AmF4, Np(NO3)4, UO2, U(SO4)2, UF4

1963–1967

SM-35,35A Pu(NO3)4.5H2O, Pu(NO3)6, PuO2, Pu(C2O4)4, Pu(O2).5H2O, Pu(OH)4, 

PuF4, PuCl4

1961–1965

Pu(NO3)4, Pu(NO3)4.5H2O, PuO2, PuO2.X H2O, Pu(C2O4)4, Pu(OH)4 1965–1967

SM-38 (SM-I) Pu(NO3)4, PuO2, Pu(SO4)2, PuF4, Am(NO3)4, AmO2, Am(SO4)2, 

AmF4, Np(NO3)4, NpO2, Np(SO4)2, NpF4

1963–1967

Np(NO3)4, UO2, U(SO4)2, UF4, Pu(NO3)4.5H2O, Pu(NO3)6, PuO2, 

Pu(C2O4)4, PuO2

1965–1970

SM-39 Pu(NO3)4.5H2O, Pu(NO3)6, PuO2, Pu(C2O4)4, PuO2.5 H2O, Pu(OH)4, 

PuF4, PuCl4

1961–1965

Pu(NO3)4, Pu(NO3)4.5H2O, PuO2, PuO2.X H2O, Pu(C2O4)4, Pu(OH)4 1965–1967

SM-58, 59 (A&B) Pu(NO3)4, PuO2, Pu(SO4)2, PuF4, Am(NO3)4, AmF4, AmO2, 

Am(SO4)2, Np(NO3)4, NpO2, Np(SO4)2, NpF4, U(NO3)4, UO2, 

U(SO4)2, UF4

1963–1967

SM-60 PuO2 1965–1967

SM-61,62 PuO2, Th-232 (EDTA and citrates acted like chelating agents) 1961–1967

SW Building

The SW (Semi-Works) Building is similar to R Building in that it consists of many laboratories engaged 

in a variety of R&D, analytical, recovery, and surveillance activities. The Old Cave and New Cave 

areas consisted of several rooms that were set up for “hot” work with several types of alpha and 

gamma radiation and project capabilities. Other major programs were the thorium refinery project, 

rare isotope program, and the neutron source, 234U separation, and the tritium programs. The tritium 

programs include the enrichment, effluent capture, process development, component evaluation, 

scrap recovery, and waste solidification. 

SW Building was used in the Cotter Concentrate (St. Louis Airport Cake) program starting in the early 

1970s and terminated late in that decade. Pilot plant operations in SW were to recover Th-230 and 

Pa-231. Table 2-6 lists the approximate composition of Cotter Concentrate.

Table 2-6. Cotter Concentrate 

composition.a

Component Grams per drum

Uranium oxide 21,740

Th-232 99.9

Pa-231 0.060

Th-230 11.1

a. 47% average moisture content.

The Old Cave was built in the early 1950s and occupied approximately 1,000-ft2 area in the SemiWorks (SW) Building. Radium-226 and 227Ac were processed from 1951 to 1955 in this area. This 

process could result in possible contamination that required decontamination efforts at various times 

during operations. From 1955 until 1959, decontamination and decommissioning (D&D) activities 

occurred in the Old Cave as manpower and budgets permitted. The cave structure was removed, 

including the exhaust systems. In March 1959, the Old Cave was cleaned and decontaminated.

SW-19 was the Old Cave, where radium-actinium separation and processing was conducted. The 

area was originally drained by a concrete channel and sumps but later filled with several feet of gravel 

and concrete due to high concentrations of radium and radon. By 1957, the area was filled over with 
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additional concrete for radiation protection purposes. SW-19 had a history of elevated radon 

concentrations that were reduced by ventilation of the underground tunnel in 1980. NIOSH is unable 

to put an upper bound on the radon exposures in SW-19 until the point at which a ventilation system 

was installed in early 1980 (before March 5, 1980) to vent SW Building tunnel air. The lack of 

sufficient information to bound the dose from radon and its progeny formed the basis for the SEC 

class definition in SEC-00171.

SW-22 was the New Cave and had few radon problems.

The radionuclides and their respective compounds that were present in SW-1A cave (EG&G 1995) 

include: 

Radium-226 Radium carbonate

Actinium-227 Radium nitrate

Radium bromide Actinium oxalate

Actinium bromide Potassium-40

Radon and progeny Thorium-228, -229, -230

Table 2-7 summarizes rooms, dates, and radioisotopes for SW Building.

Table 2-7. Radionuclides and related compounds for SW Building. 

Room Radionuclides and related compoundsa Dates used

SW-2 H-3 1973–present

SW-8 H-3, tritides(Li, Ba, Ti, Ca, U-238, others), U-235 1957–present

Xe (all isotopes) 1957–1960

U(238)(D,T), Li(D,T), Ba(D,T), Ti(D,T) 1960–1985

SW-9 H-3, tritides (Type F, S), 1965–present

U(D,T), Li(D,T), U/Al(D,T), other tritides (Type F, S) 1989–present

SW-10 H-3 1967–1972

SW-11 to 16 Ru-106, Cs-137, Sb-125, Te-121,127, Zr-93, -95, Nb-94, Sr-90, 

Pu-238, -239, Y-88, -90, -91, rare earths (especially Ce)

1951–1953

Th-228, -232, U-238, Ra-224, -228, Th-232 progeny 1955

Fe-55, -59, Al-26, Ca-45, Co-60, Pa-231, Cu-65 1956

H-3, Li tritide 1959–1965

H-3, U(D,T), Li(D,T), LiO(D,T), U-238, U-235, sOBT, other tritides 

(Type F)

1959–1978

H-3, U-238, U tritide 1964–1974

H-3, U(D,T), U-238, Pu-239, other tritides (type F, S) 1968–present

H-3, tritides (type S) 1964–1975

H-3 oxide 1975–1985

H-3, U-238, sOBT, tritides (Type F) 1975–1978

SW-19 (Old Cave) Ra-226, Ra(CO3), Ra(NO3)2, RaBr2, Ac-227, Ac(C2O4)4, AcF4, K-40, 

Th-228, -229, -230, Rn-219, -220,- 222 and progeny

1951–1953

H-3, Pu-239, U-238, U-235, tritides (Type F, S), Rn-222 and 

progeny

1962–1988

H-3, Pu-239, U-238, tritides (Type F) Ra progeny 1973–present

SW-20, 21 H-3 1961–1973

SW-22 (New Cave and 

Laboratory Area)

U-232, -233, Th-228, -229, Ra-224, -225, Ac-225, Fr-221, At-217, 

Th-228 progeny

1966–1975

Th-230, -232, U-234, -235, -238, Pa-231, Ac-227, Ra-223, -224, 

-226, Ac(NO3), AcO2.

1970–1979

Po-208, -209, -210, Po-210 progeny 1976–1979

Pu-238, Pu-239, U-233 (type F, M) 1984–1986

SW -128 to 130, 134 Th-230, -232, U- -234, -235, -238, Pa-231, Ac-227, Ra-223, -224, 

-226

1970–1979
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Room Radionuclides and related compoundsa Dates used

SW-132 Th-230, -232, U-234, -235, -238, Pa-231, Ac-227, Ra-223, -224, 

-226, Ac(NO3), AcO2

1970–1979

Po-208, -209, -210, Po-210 progeny 1976–1979

SW-136, 137 Th-230, -232, U-234, -235, -238, Pa-231, Ac-227, Ra-223, -224, 

-226, Ac(NO3), AcO2

1964–1979

SW-140 Ac-227, Ac(NO3)2, AcO2 1964–1968

Th-230, -232, U-234, -235, -238, Pa-231, Ac-227, Ac(NO3), AcO2, 

Ra-223, -224, -226

1974–1979

Po-208, -209, -210, Po-210 progeny 1976–1979

SW-142 Ra-226, Ra(CO3), Ra(NO3)2, RaBr2, Ac-227, Ac(C2O4)4, AcF2, K-40, 

Th-228, -229, -230, Po-208, -209, -210, radon and progeny

1950–1961

H-3, Li tritide 1959–1969

H-3, U-238, U(D,T), Pu-239, other tritides (Type F, S), U-233 1969–1985

SW-146, 147 H-3, U-238, U(D,T) 1967–1985

Tritiated stainless steel 1985–present

SW-149, 149A All radionuclides in SW Building 1965–1968

H-3, HTO, tritiated organics 1969–present

SW-150, 152 H-3, U-238(D,T), other tritides (Type F, S) 1968–present

H-3, U-238 tritides (Type F, S) 1973–present

SW-200 H-3 1958–present

SW-202 Po-210 1958–1962

H-3 1963–present

SW-205 H-3 1958–present

SW-208 H-3, U-238(D,T), Pu-239, other tritides (Type F) 1965–present

SW-210 H-3, U-238(D,T), Pu-239, other tritides (Type F) 1968–1989

SW-219 Pu-238/Be, Pu-239/Be, Am-241, Pu-239 1962–1965

Po-210, Pu-238, -239 1966–1971

H-3 1968–1978

H-3, U-238(D,T), tritides (Type F, S) 1968–1980

H-3, U-238(D,T), tritides (Type F) 1985–present

SW-231 H-3, HTO 1970–present

SW-238, 240 H-3, U-238(D,T), U-238, U-235, natural U, other tritides (Type F, S) 1968–present

a. sOBT = physiologically soluble, organically bound tritium.

T Building

T (Technical) Building was host to a number of R&D and production programs with various 

radioisotopes. The two major programs were the polonium and tritium programs. From 1949 to 1973, 

210Po programs included processing and separation, fuels R&D, neutron source, and other R&D and 

production programs. This work was performed on the first and second floors of T Building.

An extensive renovation program from 1966 to 1968 prepared the way for additional R&D work, but 

the renovations were never used due to unanticipated funding reductions. T Building was essentially 

dormant from 1969 to 1972 due to this loss of funding. Tritium programs resumed in the 1970s.

Other activities in T Building included nondestructive testing, environmental testing, gamma and mass 

spectroscopy, calorimetry, neutron activation analysis, and safeguards R&D. Table 2-8 summarizes T 

Building rooms, dates, and radioisotopes.

Table 2-8. Radionuclides and related compounds for T Building. 

Room Radionuclides and related compounds Dates used

T-1W, 2W, 4E Pu-238, -239, U-233,- 235, -238, H-3 1965–1987

T-5W H-3, HTO 1956–1962

1975–1982

T-5E Pu-238, -239, H-3, Co-60, Ir-192, Fe-55, -59, Ra-226, Am-241, 1955–present
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Room Radionuclides and related compounds Dates used

Cd-109

T-8 Po-210 1949–1965

T-9, 9A H-3, Pu-238 (encapsulated) 1987–present

T-13 Po-210 1949–1953

T-15B, 18 Neutron generator, neutron activation on surfaces 1963–present

T-16A H-3, tritiated organics 1984–present

T-19, 19A Pu-238, -239, H-3, Co-60, Ir-192, Fe-55, Ra-226, Am-241, Cd-109; 

all were encapsulated

1985–present

H-3, tritiated organics 1985–present

T-20 No radioactive work performed 1985–present

T-22 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Z-65, Cr-55, V-52, 

Ga-70,72, Cs-137, Sr-90, Se-75, Ag-112, Te-121 -134, Hg-203

1949–1969

Pu-238, -239 1979–present

T-25 to 27 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70,72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

Pu-238,239 (encapsulated) 1979–present

T-28 to 35 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

T-36, 36A Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

Classified 1985–present

T-37 H-3, U-238(D,T), Pu-238 (encapsulated), tritiated organics 1985–present

T-40 H-3, Pu-238 (encapsulated) 1985–present

T-41 H-3 1985–present

T-46 Po-210 1949–1969

T-48 to 50 H-3, U-238, tritides (Type F, S) 1983–present

T-53 to 55, 55A Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

T-57 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1971

H-3 1985–present

T-58 H-3 1985–present

T-59 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

H-3, U(D,T) 1985–present

T-61, 61A Po-210, Pu-238, -239 1960–1963

Po-210 1964–1966

H-3, U(D,T) 1973–present

T-63 H-3, HTO 1973–present

T-72 to 75, 92, 93, 96

to 98

Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

T-99 AlCl3, BiCl4, Ag-Po, Te-Po, PoCl2, Po-210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1947–1969

H-3 1984–present
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Room Radionuclides and related compounds Dates used

T-100 to 104 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

H-3 1972–present

T-208A Pu-238, -239, H-3, Co-60, Ir-192, Fe-55, Ra-226, Am-241, Cd-109, 

Po-210; all were encapsulated

1947–present

T-229 Po-210, Pu-238, -239 1963–1964

Rn-222, Po-210,214,218, Bi-210, Pb-210,214 1978–1988

Pu-238, -239 (encapsulated) 1989–present

T-234 H-3, U-238 tritides, other tritides (Type F) 1988–present

T-236 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1973

H-3, U-235, -238, -239, Pu-238, -239 (Pu was encapsulated) 1985–present

T-237 Ag-Po, Te-Po, PoCl2, Po-208, -209, -210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1971

H-3, Pu-238, -239 (Pu was encapsulated) 1985–present

T-238 H-3, Pu-238, -239 (Pu was encapsulated) 1985–present

T-242 Po-210 1949–1964

T-243 H-3, HTO 1956–1982

T-245 Po-210 1949–1969

Pu-238 (encapsulated) 1968–1974

T-246 H-3 1972–1980

T-247 Po-210, classified 1949–1958

Po-208, -209, -210, rare-earth polonides, Pm-147 1966–1969

T-248 to 259 Po-210, neutrons 1949–1965

Room T-257 only, orphan sources 1993–present

T-260 Po-210 1949–1969

Po-208, -209, -210, rare-earth polonides, Pm-147 1966–1969

T-266, 267 Po-210, Bi-209, -210 1949–1969

Po-208, -209, -210, rare-earth polonides, Pm-147 1963–1966

H-3, U-238(D,T), other tritides (Type F) 1988–present

T-270 Po-210, Bi-209, -210 1949–1963

T-274 External dose only 1948–1971

Po-210, Bi-210, Fe-55, -59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, 

Zn-65, Cr-55, V-52, Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, 

Te-121 -134, Hg-203

1966–1969

H-3, U-238(D,T) 1986–present

T-275, 276 AlCl3, BiCl4, Ag-Po, Te-Po, PoCl2, Po-210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

T-277, 279 Am-241, Pu-239, neutrons 1949–1964

Po-210 1949–1969

Bi-209, -210 1964–1969

T-300A Orphan sources, sources left in containers

T-307 Po-210 1949–1964

H-3 1972–present

T-310 AlCl3, BiCl4, Ag-Po, Te-Po, PoCl2, Po-210, Bi-210, Po(NO3)2, Fe-55, 

-59, Si-31, Co-60, Pb-209, Sb-124, Sn-121, Zn-65, Cr-55, V-52, 

Ga-70, -72, Cs-137, Sr-90, Se-75, Ag-112, Te-121-134, Hg-203

1949–1969

Pu-238, -239, -240, -241, Pm-147, U-233, -235, Am-241, H-3 1969–1983

Pu-238, -239 (encapsulated) 1986–present

T-311 Po-210 1949–1969

Pu-238, -239 (encapsulated) 1986–present
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Room Radionuclides and related compounds Dates used

T-319 Pu-238, -239, -240, -241, Pm-147, U-233, -235, Am-241, H-3, HTO 1949–present

WD and WDA Buildings

WD Building, which became operational in February 1949, is the central facility at Mound for the 

treatment of radioactive liquid wastes. From its inception, this facility included a low-level alpha 

wastewater system, with SW, R, PP, SM, HH, T, B, and H Buildings as sources. On arriving at WD 

Building, wastewater was precipitated, coagulated, and filtered, and the sludge is solidified so it can 

be shipped off the site. The supernatant from the clarifloculator is filtered, neutralized to the proper 

pH, monitored to see if below standard, and released to the Great Miami River.

The WDA Building alpha wastewater treatment facility was built in 1966 as an annex to WB Building 

for the treatment of plutonium wastewater from the PP and SM Buildings. It was designed as both a 

high-risk drumming station and a low-risk wastewater treatment facility. Table 2-9 summarizes rooms, 

dates, and radioisotopes for WD and WDA Buildings.

Table 2-9. Radionuclides and related compounds for WD and WDA Buildings. 

Room Radionuclides and related compounds Dates used

WD-1, 8, 101, 104 Ag-Po, Te-Po, PoCl2, Bi-210, Po(NO3)2, Si-31, Sb-124, Sn-121, 

Zn-65, Cr-55, V-52, Ga-70, –72, Se-75, Ag-112, Hg-203

1949–1958

Am-241, Ac-227, Ra-223, -226, Ac(C2O4)4, Th-228, -229, -230, 

U-234, -235, -238, Pu-238, -239, Po-208, -209, -210, Cs-137, 

Pa-231, AcO2, Ac(NO3)2, AcBr4, AcF4, K-40, Ba(NO3)2, Np-237, H-3, 

rare-earth isotopes, tritiated octane, Co-60, Sr-90, Fe-55, -59, 

Te-121 to -134, UO2

1949–1990

Th-228, -232, Ra-224, -228, U-238 1955

Pu-236, -238, -239, -240, -241, -242, Pu(NO3)4, PuO2, Pu(SO4)2, 

Pu(OH)4, PuF4 (also nitrate, sulfate, oxide, and fluoride compounds 

of Am-241, Np-237, U-234)

1961–1974

Th-230, -232, U-234, -235, -238, Pu-238, -239, Pa-231, Ac-227, 

Ra-223, -224, -226

1974–1979

WD-9 H-3, U-239(D,T), U-235, -238, -239, Pu-238, -239, Am-241, Rn-222, 

Po-208, -209, -210 Po-210 progeny, Bi-210, -214, Pb-210, -214, 

Ra-223, -224, -226 Ra progeny, U(D,T), Li(D,T), U/Al(D,T)

1973–present

WD-10 Pu-236, -238, -239, -240, -241, -242, Pu(NO3)4, PuO2, Pu(SO4)2, 

Pu(OH)4, PuF4 (also nitrate, sulfate, oxide, and fluoride compounds 

of Am-241, Np-237, U-234)

1961–1974

WD-107 Cs-137, Am-241, Np-237, U-235,238 1976–1981

WD-108 Pu-236, -238, -239, -240, -241, -242, Pu(NO3)4, PuO2, Pu(SO4)2, 

Pu(OH)4, PuF4 (also nitrate, sulfate, oxide, and fluoride compounds 

of Am-241, Np-237, U-234)

1949–1981

WDA-110 Pu-236, -238, -239, -240, -241, -242, Pu(NO3)4.5H2O, Pu(NO3)6, 

PuO2, Pu(C2O4)4, Pu(O2).5H2O, Pu(OH)4, PuF4 (also nitrate, sulfate, 

oxide, fluoride compounds of Am-241, Np-237, U-234)

1966–1970

H-3 1967–present

WDA-112 Pu-236, -238, -239, -240, -241, -242, Pu(NO3)4.5H2O, Pu(NO3)6, 

PuO2, Pu(C2O4)4, Pu(O2).5H2O, Pu(OH)4, PuF4 (also nitrate, sulfate, 

oxide, fluoride compounds of Am-241, Np-237, U-234)

1966–1979

Cs-137 1980–1984

WDA-113 Cs-137, Co-60, I-131, Pu-238, -239 1979–1994

WDA-118A Co-60, Cs-137, I-131, Sr-90 1977–1981

WDA-118B Pu-238, -239, H-3 1975–1985

Co-60, Cs-137, Mn-54, Sr-90 1981–present

WD-penthouse Th-230, -232, U-234, -235, -238, Pu-238, -239, Pa-231, Ac-227, 1949–present
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Ra-223, -224, -226, -228, Co-60, Cs-137, Np-237, Sr-90, Po-208, 

-209, -210, Am-241, H-3, Te-121-134, Fe-55, -59

Warehouse 9 (1953)

All of the drums stored in Warehouse 13 from the plutonium-uranium extraction (PUREX)/bismuth 

phosphate materials decontamination were moved to Warehouse 9 in preparation for shipment off the 

site. The following radionuclides (as well as their compounds) are of equal concern: 

Antimony-125 Ruthenium-106

Cesium-137 Strontium-90

Niobium-94 Tellurium-121 and -127

Plutonium-238 and -239 Yttrium-88, -90, and -91

Rare earths (especially cerium) Zirconium-93 and -95

Warehouse 13 (1953)

This warehouse was used for the storage and shipment of several drums of sludge from the 

PUREX/bismuth phosphate decontamination program. The settling and mixing tanks were also taken 

there. The following radionuclides (as well as their compounds) are of equal concern: 

Antimony-125 Ruthenium-106

Cesium-137 Strontium-90

Niobium-94 Tellurium-121 and -127

Plutonium-238 and -239 Yttrium-88, -90, and -91

Rare earths (especially cerium) Zirconium-93, -95

This warehouse was also used for temporary storage for drums of low-level contamination from the 

226Ra/227Ac decontamination operations. Radioisotopes of concern and their compounds are:

Actinium fluoride Radium nitrate

Actinium oxalate Radium-226

Actinium-227 Radon and progeny

Barium nitrate Thorium-228

Potassium-40 Thorium-229

Radium bromide Thorium-230

Radium carbonate

Actinium-227 is the major radionuclide of concern. Radium-226 and 228Th are of nearly equal 

concern, and 208Po, 209Po, and 210Po are of much less concern. The remaining isotopes are of small 

concern.

Warehouse 15 (1955 to 1961)

This warehouse stored 1,650 t of the 232Th refinery program (Monex) sludge. It was highly corrosive 

and continually leaked through the barrels causing much contamination. More than 34 isotopes were 

identified from the feedstock of this program with most being nonradioactive. Radioisotopes of 

concern and their compounds are:

• Radium-228 and -224

• Thorium-232 progeny (especially thallium-208)

• Thorium-232 and -228

• Uranium-238
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 25 of 35

Thorium-228 and -232 and 224Ra are equal as major radionuclides of concern. Uranium-238 is a 

secondary concern. However, when considering the quantity or mass of radionuclides, and not 

activity, 99% are 232Th.

Building 21

This building was constructed in 1964 for bulk storage of thorium ores and sludge from the old Monex 

project, a 232Th refinery program. It was originally designed like a silo with no doors or windows; 

oxalate sludge was stored in one side and hydroxide sludge in the other. Until 1973 at least 117 

55-gal leaky drums remained outside the building. Contamination of the surrounding grounds 

occurred from fugitive dust from the dumping of this sludge into this silo. From October 1974 to July 

1975, the sludge was repackaged in 55-gal drums and shipped off the site. Radionuclide contents of 

the sludge were primarily thorium isotopes, rare-earth isotopes, uranium, and others.

A total of 1,252 55-gal drums of Cotter Concentrate were stored in Building 21 from 1975 until 1987 

when they were shipped off the site. This concentrate contained significant quantities of the following, 

which are radionuclides of concern:

• Actinium nitrate

• Actinium oxide

• Actinium-227

• Protactinium-231

• Radium-223, -224, and -226

• Thorium-230 and-232

• Uranium-234, -235, and -238

Thorium-230 was the major radionuclide of concern with more than 95% of the activity.

Fourteen elements beside the isotopes listed above are in the Cotter Concentrate. There is no 

indication that these 14 elements are radioactive.

The surrounding grounds served as storage for 238Pu waste packages in 1967. There was leakage of 

the plutonium waste packages. The area around Building 21 was contaminated because of the 

leakage of the Monex sludge drums, the debris from dumping sludge through the roof, and 

repackaging into drums.

Building 34

This building has a dual purpose: it was a drop test area for waste packages and an area for 

simulation of pyrophoric metal training for the firefighters. The empty low specific activity (LSA) 

containers were dropped in various ways to test and ensure their structural integrity. Similar tests 

were done on drums.

Depleted uranium and metal shavings of various types were used in firefighting practice to simulate 

pyrophoric situations. Radioisotopes of concern include 238U oxide.

Building 50

Building 50 is designated as the assembly and testing building for RTGs. In Building 50, RTGs are 

assembled in an inert atmosphere. All plutonium used as the heat source is encapsulated, which 

gives little probability for a radionuclide release. External dose is still possible from gamma and 

neutron flux.

A testing program is associated with the RTG program. Approximately 20 tests (vibration, space 

simulation, extreme heat, extreme cold, shock, vacuum performance, etc.) are done on the RTG 

module.
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Building 59

This building contains a subcritical assembly, which has the ability to produce fission products. 

However, all fission products were sealed in aluminum containers, so the probability of contamination 

is remote. The water surrounding the containers inside the assembly is constantly monitored and 

contamination has been observed.

Californium-252 and enriched uranium were used for irradiation. These radioisotopes were 

encapsulated in metal cladding, so there is no concern for internal dosimetry. Some intentional 

irradiation is done, with the major contaminants being 55Fe, 59Fe, and 60Co. Radionuclides of concern 

are:

• Californium-252

• Cobalt-60

• Iron-55 and -59

• Uranium-234, -235, and -238

The historical radionuclides of major concern were 252Cf and 235U, equally. This building has not been 

operational since 1990 and is not likely to operate again. In the future, radionuclides of concern will 

be 235U and 59Fe in the form of rust during building demolition.

Building 68

This building functions as a D&D staging area and handles the radionuclide waste from R Building.

A corollary activity of this area is to perform testing on empty LSA containers. These are dropped in 

various ways to test and ensure their structural integrity. Similar tests are also done on drums. 

Radioisotopes of concern are 238Pu oxide and 239Pu oxide.

B Building

From around 1950 to about 1955, this building was used for biological research of the effects of 210Po, 

227Ac, and other alpha emitters on animals. The results were used to estimate the effects of 

radionuclides that were used at Mound on humans. Biological testing was discontinued in about 1955 

when detonator manufacturing began.

A Biological Research Quarterly from June 1954 (EG&G 1995 p. 263) discusses mice and rat 

experiments, which were conducted over a 2-year period with 210Po. In another experiment rats were 

given a 227Ac solution that also contained 227Th, 223Ra, 219Rn, 215Po, and 211Bi.

A report by Anthony et al. (EG&G 1995 p. 263) discusses experimental results of single acute and 

multiple exposures of 210Po to rats with higher dosages of polonium than previously reported. In 

addition, studies with plutonium were done with a special emphasis on 238Pu. Other reports discuss 

experimental work using 226Ra and 227Ac.

Room B-146

This was a laboratory where early research was done. Radioisotopes of concern and their 

compounds are:

Actinium-227 Polonium-215

Bismuth-211 Radium-223 and -226

Plutonium-238 Radon-219

Polonium-210 Thorium-227

Polonium-210 was the major radionuclide of concern with 227Ac being secondary. B-Building was 

decontaminated by July of 1955.
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Rooms E-141, -142, -144, -155

In use from 1981 to the present, Room E-141 uses small amounts of radionuclide standards of 

varying amounts and kinds as tracers for environmental testing. The tracers are in liquid form with 

only 210Pb being encapsulated. They are used and stored in Room E-141, and are used in Rooms 

E-142, -144, and -155, which are also environmental laboratories. Radionuclides of concern are:

Plutonium-238, -239 Thorium-229, -230

Tritium Uranium-232, -234, -236, -238

Lead-210

Rooms E-174, -175, -177, -185, -194

These rooms have been used for cold storage and, therefore, were thought not to contain 

radionuclides. However, recent surveys found items in these rooms contaminated with alpha, beta, 

and gamma radiation. The following specific results were found:

• Room E-174, alpha from an unknown source; 

• Room E-175, beta and gamma from an unknown source; 

• Room E-177, beta and gamma from a 235U rod, epoxy metallurgical sample, metal chips; 

• Room E-185 (~1985-present), alpha and beta on metallurgical sample contaminated with 235U, 

a second sample with suspected contamination from 232Th; and

• Room E-194, alpha from possible plutonium, beta and gamma from possible 235U or 238U. 

An overview of operations in E Building includes nitrate and chloride solutions of:

Lead-210 Thorium-229 and -230

Plutonium-238, -239, and -242 Tritium

Polonium-210 Uranium-232, -234, -235, -236, and -238

Plutonium-238 was the major radionuclide of concern with 210Po second and tritium third.

H Building

Although this building houses many innocuous functions such as the credit union and change rooms, 

there are activities that have the potential for radionuclide intakes.

The laundry had a “hot laundry” ability to handle clothes that were exposed to radionuclides, which is 

the primary reason the structure was built. Bioassay and other environmental laboratories in H

Building have the potential for low levels of exposure. Most radionuclides are tracer nitrate and 

chloride solutions of 238Pu, 239Pu, 242Pu, 232U, 236U, and 229Th. Tritium and 210Po could be included. It 

has been suggested that 226Ra, 228Th, and 227Ac be included in the list.

Radionuclides and related compounds of concern are:

Actinium-227 Thorium-228 and -229

Plutonium-238, -239, and -242 Tritium

Polonium-210 Uranium-232 and -236

Radium-226

Plutonium-238 was the major radionuclide of concern with 210Po second and 227Ac third.
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 28 of 35

I Building

I Building refers to the Isolation Building, where low-level counting of bioassay (urine and fecal) 

samples and environmental counting for soil, vegetation, etc., were performed from 1955 to the 

present. There is little concern about the possibility of uptakes. This area is used for nondestructive 

testing and the assembly of explosive devices. No radionuclides are used.

M Building

Room M-20 had a Livermore dry box. In addition, 238U was machined in this building.

R&R Building

This small building between the SM and PP Buildings was used for sorting plutonium solid waste, 

some of which could be reprocessed. The compound forms of the plutonium and lung solubility types 

are as follows:

• Plutonium oxide, PuO2, type S; this could also take the form of a plutonium oxide hydrate—

PuO2.XH2O; 

• Plutonium hydroxide, Pu(OH)4, type S; and

• Plutonium nitrate, Pu(NO3)4, type M; this could also take the form of plutonium nitrate 

pentadhydrate, Pu(NO3)4.5H2O. 

Plutonium-238 was the major radionuclide of concern; 239Pu was second.

SD Building (57, 112, and 113) (1947 to 1970)

The SD Building was a sanitation building that could have had some contaminated sludge from 

broken lines or pipes. Contamination would have been minor in concentration but could have 

contained radionuclides from polonium processing. Radionuclides of concern and related compounds 

are:

Antimony-124 Polonium-208, -209, and -210

Bismuth-210 Selenium-75

Cesium-137 Silicon-31

Chromium-55 Silver polonide

Cobalt-60 Tellurium polonide

Gallium-70 and -72 Silver-112

Iron-55,59 Strontium-90

Lead-209 Tellurium-121 and possibly Te--134

Mercury-203 Tin-121

Plutonium-238 and -239 Vanadium-52

Polonium chloride Zinc-65

Polonium nitrate

Polonium-210 was the major radionuclide of concern, with 238Pu second and 65Zn third.

Building 19

This 4,800-ft2 Quonset hut contains a small office and an area for storing Comprehensive 

Environmental Response, Compensation, and Liability Act (CERCLA) materials. The building was 

constructed in 1962 for Mound Salvage storage and sales. Since 1988 it has been used to store 

CERCLA soil drums and empty drums. Low-level waste (LLW) and LSA drums have also been stored 

in this building. Plutonium-238 and 232Th were the primary isotopes in the LLW and LSA drums.
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 29 of 35

Building 22

Building 22 is a 9,090-ft2 one-story steel-frame building that was constructed in 1966 for office space 

and storage of items to be sold. In 1995 the building was modified to handle radioactive LLW solid 

waste.

Building 23

Building 23 is a 3,422-ft2 one-story steel-frame building that was constructed in 1966 as a warehouse 

used for preparation and shipping of LLW. It was later used to store mixed and transuranic (TRU) 

mixed waste. The building was modified in 1994 to contain spills.

Building 30

Building 30 contains a counting laboratory. Liquid scintillation counting for tritium and gross alpha and 

beta counting were performed in this building. The facility performed gamma scans of drums and 

boxes. Several years ago the facility was converted from office space to a counting laboratory.

Building 31

Building 31 is a 3,000-ft2 metal fabricated building that was constructed in 1966. The building is used 

for storage and preparation of LLW waste.

Building 31A

Building 31A is a 2,650-ft2 metal fabricated building that was constructed in 1986 to store LSA and 

TRU waste. The building is currently used for storage of TRU wastes.

Building 35

Building 35 is a 2,500-ft2 metal fabricated building that was constructed in 1967 for X-ray and eddy-ray 

current nondestructive testing. The facility was also used as the control room for the 252Cf multiplier 

neutron radiography facility.

Building 39

Building 39 is a 3,515-ft2 metal fabricated building that was constructed in 1967 to build fiberglass 

wooden boxes for radioactive trash for the D&D activities. Indications are that gamma spectroscopy 

on these boxes was also performed in this building. From 1984 to 1988 the building was either 

inactive or used for storage. Since 1988 the building has been used as a maintenance shop.

Building 45

Building 45 is a 9,582-ft2 concrete building that was constructed in 1967. The building is the health 

physics calibration laboratory. The facility has equipment for calibration of health physics 

instrumentation and dosimeters. The facility houses a well calibration area, a beta calibration area, a 

calibration and repair area, a dosimeter preparation area, an X-ray calibration area, and a low-scatter 

neutron and maximum field calibration area.

Building 58

Building 58 is a 6,100-ft2 concrete building that was constructed in 1977. The building is the alpha 

and beta filter and plenum exhaust for SW Building.

Building 72

Building 72 is a 2,400-ft2 metal frame building that was constructed in 1984. The building is the site 

hazardous storage waste facility. Liquid scintillation vials are stored in this facility.

Building 90

Building 90, which was constructed in 1985, housed the unit controls and feed operations for the retort 

unit (rotary kiln thermal treatment unit) located in the burn area. Operations ended in January 1996.
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Building 94

Building 94 is a 1,240-ft2 metal building that was constructed in 1985. The building is used for 

CERCLA contractor staging and storage of soil and water samples.

Building 123 (Rubb)

In addition to fulfilling a variety of uses, this temporary structure has also had different names, 

including WTS Rubb from 1989 into the 1990s and the Rubb Building later in the 1990s. More 

recently, it has been called Rubb Building 123.

Rubb Building 123 was constructed in 1989 and was deconstructed in 2001. The building was used 

to store heavy equipment in 1989. Beginning in 1994, LSA boxes containing soils from the WTS line 

cleanup were emptied and sampled in the building. The boxes being opened were randomly selected 

from a population of nearly 700 boxes to achieve a 95% confidence level. The purpose of this 

process was to conduct content verifications of the boxes. The results of this verification sampling 

eventually led to the ability to ship the boxes as LLW.

In the 1990s the Rubb Building 123 was also used for storage of heavy-duty equipment for the D&D 

group. Heavy-duty equipment stored in this structure was likely used in the demolition of site 

buildings and in the cleanup of contaminated areas on the plant site.

The Brickmaker 

The Brickmaker, which was built in 1992, was a temporary structure to house equipment to compress 

and dewater low-level radioactively contaminated soils into extruded bricks that could be placed in 

LLW boxes for disposal off the site. The project area consisted of two temporary steel-framed Rubbbrand buildings, an office trailer, and a lined in-ground pit to receive water from the process.

Building 124, Consolidated Waste Processing Facility (CH2M Hill 2003) 

Building 124, also known as the Consolidated Waste Processing Facility (CWPF), was constructed in 

1998. Building 124 performed various volume reduction or repackaging functions that are routinely 

performed at Mound. The building processed LLW from various demolition sites and safe shutdown 

activities as well as legacy waste streams. Building 124 is in an Underground Radiological Materials 

Area.

The Auditable Safety Analysis ASA included a list of expected process input materials, as described 

in Section 2.3. The list included, but was not limited to:

• Nonstructural equipment and debris (soft objects such as rags and bags for compaction); 

• Structural steel for decontamination, size reduction, and release; 

• Soils and other demolition debris for blending to reduce the radioactive material content to 

meet specific waste profiles; 

• Drums, boxes, and other types of containers in order to puncture the container lids to vent gas, 

sample and analyze the released gas, and to install filter vents; 

• Liquids generated by the air recirculation unit or tritium-contaminated liquids collected during 

opening or repackaging containers with tritium contamination; 

• Various types of waste packages for sampling, consolidation, or repackaging, or other 

activities that ensure that the waste is packaged in a form suitable for shipment off the site and 

final disposal.
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At Building 124 the stack was monitored for potential air emissions of:

• Tritium

• Plutonium-238

• Plutonium-239 and -240

• Uranium-233 and -234

• Uranium-238

Area 8, Thorium Contaminated Soils from Areas 1 and 9

The area is northwest of Building 31 on the SM/PP hill on the eastern side of Mound site. The area is 

approximately 25,000 ft2

. Soil was buried in this area from decontamination activities from 

repackaging of 232Th sludges in 1965 and 1966. Plutonium-238 was detected at a maximum 

concentration of 24 pCi/g. The maximum thorium concentration was 254.3 pCi/g.

Area 10, Debris from Dayton Units

The area is west of Building 30 on the slope of the SM/PP hill on the East Central portion of Mound 

site. It was used for disposal of contaminated concrete from Dayton Units. One hundred and sixty 

truckloads from Unit IV and 100 truckloads from Unit III were deposited here. The area is 

approximately 15,000 ft2

. The primary contaminant was 210Po. Soil was buried in this area in 1950.

Area 12, Thorium Contaminated Soil

The area is west of Building 38 on the SM/PP hill on the East Central portion of Mound site. Soil 

contaminated with 232Th and 238Pu from SM Building and with thorium from Area 1 were placed in this 

area in 1965.

WTS Pipeline

The pipeline line ran from SM Building and Building 38 to the WD Building. In 1969 the high-risk 

waste line ruptured below the WD Building. The pipeline may have leaked in other locations as well 

along its path.

Buildings without Radionuclide Activity

The following buildings have not supported radionuclide activities: 1, 2, 3, 13, 14, 16, 17, 24, 25, 26, 

27, 28, 29, 33, 36, 37, 40, 41, 42, 43, 44, 46, 47, 49, 51, 55, 56, 60, 61, 63E, 63W, 65, 66, 67, 69, 70, 

71, 73, 74, 79, 85, 87, 88, 49, 91, 92, 93, 95, 96, 98, 99, 100, 101, 102, 104, 105, 106, 120, 

A (Administration), C (Old Cafeteria), COS, G, Generator-1, Generator-6, GH, GP-1, GP-5, GP-8, GP44, GS, GW, Modular 4, OSE, OSW, P (Power Plant), PH, SST, W, WH-1, WH-2, WH-3, and 

Magazines 5, 6, 7, 8, 10, 11, 20, 52, 53, 54, 64, 80, 81, 82, 83, and 84.

2.3 ATTRIBUTIONS AND ANNOTATIONS

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

section of this document.
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 32 of 35

REFERENCES

Author unknown, 2002, The Brickmaker References to Processes and Waste Generation, February. 

[SRDB Ref ID: 14553]

Author unknown, 2003, References to Processes for the Rubb Building Located at Building 104 (a.k.a. 

Rubb Building 123), January 2. [SRDB Ref ID: 14555]

CH2M Hill (CH2M Hill Mound), 2003, Building 124 (CWPF) Structural History and Process History 

Summary Background Document, Miamisburg, Ohio, November. [SRDB Ref ID: 14557]

DOE (Department of Energy), 1993, Mound Plant Operable Unit 9 Site Scoping Report: Volume 7 – 

Waste Management, Albuquerque Operations Office, Albuquerque, New Mexico. [SRDB Ref 

ID: 11877]

DOE (Department of Energy), 1999, Work Plan for Environmental Restoration at the DOE Mound 

Site, The Mound 2000 Approach, Final (Revision 0), Albuquerque Operations Office, 

Albuquerque, New Mexico. [SRDB Ref ID: 12624]

DOE (U.S. Department of Energy), 2011, Mound Site, Miamisburg, Ohio, Fact Sheet, Office of Legacy 

Management, Grand Junction, Colorado, December 12. [SRDB Ref ID: 119815]

EG&G (EG&G Mound Applied Technologies), 1995, Mound Site Radionuclides by Location, MD22153, Issue 1, Mound Facility, Miamisburg, Ohio, June 22. [SRDB Ref ID: 3240]

EPA (U.S. Environmental Protection Agency), 2003, NPL Fact Sheets for Ohio: Mound Plant 

(USDOE), http://www.epa.gov/R5Super/npl/ohio/OH6890008984.htm (accessed 2/17/2004). 

[SRDB Ref ID: 12425]

Gilbert, K. V., 1969, History of the Dayton Project, Monsanto Research Corporation, Mound 

Laboratory, Miamisburg Ohio, June. [SRDB Ref ID: 3136]

Leavitt, M. O., 2008, HHS Designation of Additional Members of the Special Exposure Cohort under 

the Energy Employees Occupational Illness Compensation Program Act of 2000, Designating 

a Class of Employees from Mound Plant, Miamisburg, Ohio, U.S. Department of Health and 

Human Services, Office of the Secretary, Washington, D.C., March 3. [SRDB Ref ID: 80513]

Meyer, H. E., 1979, Historical Resume of Monsanto’s Operation of the Dayton Project Sites, EG&G 

Mound Applied Technologies, Miamisburg, Ohio. [SRDB Ref ID: 12701] 

Meyer, H. E., 1992, History of Mound Bioassay Programs, MLM-MV-93-93-0003, EG&G Mound 

Applied Technologies, Miamisburg, Ohio. [SRDB Ref ID: 1962]

Mound Environmental Management Project, Miamisburg, Ohio, 2000, Mound Site Process History 

Summary. (SRDB Ref ID: 49142)

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 1.

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, November 21.
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 33 of 35

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. 1, Division of Compensation Analysis and 

Support, Cincinnati, Ohio, October 5.

NIOSH (National Institute for Occupational Safety and Health), 2012, SEC Petition Evaluation Report, 

Petition SEC-00207, Division of Compensation Analysis and Support, Cincinnati, Ohio, 

September 6.

Sebelius, K., 2010, HHS Designation of Additional Members of the Special Exposure Cohort under 

the Energy Employees Occupational Illness Compensation Program Act of 2000, Designating 

a Class of Employees from Mound Plant, Miamisburg, Ohio, U.S. Department of Health and 

Human Services, Office of the Secretary, Washington, D.C., July 14.

Sebelius, K., 2012, HHS Designation of Additional Members of the Special Exposure Cohort under 

the Energy Employees Occupational Illness Compensation Program Act of 2000, Designating 

a Class of Employees from the Mound Plant, Dayton, Ohio, U.S. Department of Health and 

Human Services, Office of the Secretary, Washington, D.C., December 7. 
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GLOSSARY

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA; 

42 U.S.C. § 9601 et seq.) 

Federal law that governs the removal, remediation, and response to hazardous substance 

contamination.

curie (Ci)

Traditional unit of radioactivity equal to 37 billion (3.7 × 1010) becquerels, which is 

approximately equal to the activity of 1 gram of pure 226Ra.

decontamination

Reduction or removal of radioactive material from a structure, area, object, or person. 

Decontamination can occur through (1) treating the surface to remove or decrease the 

contamination or (2) allowing natural radioactive decay to occur over a period of time.

enriched uranium

Uranium in which processing has increased the proportion of 235U to 238U to above the natural 

level of 0.7% by mass. Reactor-grade uranium is usually about 3.5% 235U; weapons-grade 

uranium contains greater than 90% 235U.

exposure

(1) In general, the act of being exposed to ionizing radiation. See acute exposure and chronic 

exposure. (2) Measure of the ionization produced by X- and gamma-ray photons in air in units 

of roentgens.

metal tritide

Metal that absorb tritium atoms in the crystalline structure of the metal. Metal hydrides and 

tritides are the most compact way to store hydrogen or tritium. Because of that, metal tritides 

are most often used as a method of retaining or storing tritium.

pitchblende

Mineral containing uranium oxide (UOX) of variable composition ranging between UO2 and 

U3O8 as well as radium.

polonium (Po)

Radioactive element with atomic number 84. Polonium mixed or alloyed with beryllium 

provides a source of neutrons for dosimeter calibration.

plutonium–uranium extraction (PUREX)

Process for separating used nuclear fuel into components that produces pure plutonium and 

uranium along with a waste remainder. The separation uses a water-based acid dissolution of 

the used nuclear fuel.

radiation

Subatomic particles and electromagnetic rays (photons) with kinetic energy that interact with 

matter through various mechanisms that involve energy transfer. See ionizing radiation. 

radioactive contamination

Radioactive material where it is not wanted.

radioactive waste

Radioactive solid, liquid, and gaseous materials for which there is no further use. Wastes are 

generally classified as high-level (with radioactivity as high as hundreds of thousands of curies 
Document No. ORAUT-TKBS-0016-2 Revision No. 01 Effective Date: 04/01/2013 Page 35 of 35

per gallon or cubic foot), low-level (in the range of 1 microcurie per gallon or cubic foot), 

intermediate level (between these extremes), mixed (also contains hazardous waste), and 

transuranic.

radioisotopic thermoelectric generator (RTG)

Generator that obtains its power from passive (natural) radioactive decay using thermocouples 

to convert the heat of decay into electricity.

sealed source

Radioactive material encased in a capsule designed to prevent leakage or escape of the 

material.

transuranic (TRU) elements

Elements with atomic numbers above 92 (uranium). Examples include plutonium and 

americium.

tritium (hydrogen-3, 3

H, T)

Radioactive isotope of hydrogen that contains one proton and two neutrons in its nucleus. It 

decays by beta emission and has a radioactive half-life of about 12.5 years.