Hanford

Special Exposure Cohort 

Petition Evaluation Report

Samuel Glover, PhD

Research Health Scientist

National Institute for Occupational Safety and Health

Division of Compensation Analysis and Support

June 2012

Santa Fe, NM
Petition Overview

 83.14 petition received on May 3, 2012

 Proposed class definition:

• All employees of the Department of Energy, 

its predecessor agencies, and their contractors 

and subcontractors who worked at the 

Hanford Engineer Works in Richland, 

Washington, from July 1, 1972 through 

December 31, 1983
Petition Overview—cont. 

 Three existing SEC classes previously 

established at Hanford:

1. October 1, 1943 through August 31, 1946, for 

selected areas of Hanford (Petition 57)

2. September 1, 1946 through December 31, 1968, 

for selected areas of Hanford (Petition 57)

3. October 1, 1943 through June 30, 1972, for all 

areas of Hanford (this class subsumed previous 

two classes; Petition 152)
Petition Overview—cont. 

 Petition 57 requested the SEC class be 

continued through 1990

• Petition 201 (this report) represents the 

research NIOSH conducted as part of the post 

1972 review

• The remaining time period (1984 thru 1990) 

remains a subject of continuing investigation
Petition Overview—cont.

 Petition 155 also remains before the Advisory 

Board

• The petitioner’s specific evidence of accusations by the 

U.S. EPA of purposeful wrong doing by US Testing 

resulted in NIOSH determining that issues regarding 

quality of bioassay data required further investigation 

as a separate issue from the continuing Board 

evaluation of Petition 57 (1987-1989)

• The intent of NIOSH’s separate evaluation of Petition 

155 was to ensure that issues identified with US 

Testing’s non-bioassay analytical programs did not also 

adversely affect the company’s bioassay analysis 

operations in Richland, WA

• SC&A is currently preparing a report regarding the 

review of Petition 155
Update of Activities

 The Advisory Board had previously identified three 

focus areas (Am/Th/U) for Petition 152

 NIOSH prepared a number of draft reports for 

various nuclides which were used to develop 

Petition 152 and update the TBD

 NIOSH focused on activities in the post-June 1972 

timeframe, concentrating on neptunium (Np), 

uranium (HEU, 233U), and thorium (Th)

• Results of these investigations led to class proposed by 

NIOSH in the evaluation report for Petition 201

• Data gained from additional data captures will be used to 

update the TBD
Update of Activities—cont. 

 Sources of Available Information 

• ORAU Team Technical Basis Documents (TBDs)

• ORAU Team Technical Information Bulletins (TIBs) and 

Procedures

• 19 additional interviews with former employees

• Existing claimant files

• NIOSH Site Research Database (over 32000 Hanford 

related documents)

• 10 additional data captures at Hanford related to SEC 

201
Update of Activities—cont. 

 Research at Hanford has been challenging 

• Changes in contractors and missions often change the 

entire research strategy and documentation available and 

even personnel related to processes

• Theses challenges have led to focused efforts involving 

the review of large numbers of classified and unclassified 

documents

• NIOSH and the Advisory Board, with the support of DOE 

Richland, have worked to review this complex facility 

with a view to timeliness and accuracy
Neptunium

 At the conclusion of Petition 152, NIOSH’s research to 

that point indicated that the programs related to 

neptunium had ceased. Activities before July 1, 1972, 

as described in Petition 152 included:

• Area 200 from May 1, 1948 through June 30, 1972: Area 200 

neptunium-237 operations began with the crude separation of 

neptunium from metal wastes, first reported in May 1948. 

Production of neptunium nitrate in the 200 Area ceased with 

the shutdown of PUREX in June 1972.

• Area 300 from January 1, 1966 through December 31, 1970: 

Neptunium work in the 300 Area began with target-element 

fabrication beginning in 1966. Neptunium/plutonium 

separations continued into 1970. 
Neptunium—cont. 

 Continued research at Hanford led NIOSH to follow a 

series of activities that were located in the 200 and 300 

areas involving neptunium operations that were not 

addressed by Petition 152 (activities conducted after 

June 1972)

 Partial material inventories show that neptunium was 

used after June 1972 by a variety of departments at 

Hanford (e.g. Metallurgical Development, Chemical 

Technology, and Fuels Design and Development)
Neptunium—cont. 

 A number of buildings were identified as having 

continued neptunium operations after 1972 including 

(partial listing):

• Defense related metallurgical work at 231Z

• Fuels Design and Development in 308

• Research in 325 and 329

• Entries into the Q cell and J cells of Purex
Neptunium—cont. 

 Monitoring

• No bioassay prior to 1972

• Only four in vitro bioassay measurements in the Petition 

201 time-period

• All were collected the same day in September 1972

• A single wound count for 237Np was identified in the 

Hanford REX database (for a wound)
Thorium

 At the conclusion of Petition 152, NIOSH’s research to 

that point indicated that the programs related to 

thorium had ceased

• Area 100 from January 1, 1965 through December 31, 1968: 

Fuel element failures associated with the irradiation of 

thorium fuel occurred during the 1965-1970 campaigns to 

produce uranium-233

• Area 200 from January 1, 1965 through December 31, 1970: 

Major thorium operations in Area 200 began with a test of the 

THOREX process in 1965, and continued through the final 

major campaign to fabricate, irradiate, and process pelletized 

thorium-oxide targets in 1970
Thorium—cont. 

• Area 300 from October 1, 1945 through December 31, 1970: 

Site thorium operations began with trial canning in October 

1945 and continued through the final major campaign to 

fabricate, irradiate, and process pelletized thorium-oxide 

targets in 1970

 Continued research at Hanford led NIOSH to follow a 

series of activities that were located in the 200 and 300 

areas involving thorium operations that were not 

addressed by Petition 152 (activities conducted after 

June 1972)
Thorium—cont. 

 Activities included

• Preparation and shipping of 350 tons of thorium to Fernald 

(this material was left over from the THOREX campaigns and 

were slightly contaminated with 233U)

—Conducted at 203-A, 241-WR and204-S facilities

—Shipments occurred during the period 1977 through 1979 (33 

shipments total)

—Facilities required cleanup after material removal

• Other included processes which generated 

plutonium/uranium/thorium scrap which was sent to LANL

• 300 Area work included reactor fuels research

• The Thorium Oxide Fuel Development Laboratory was 

completed in mid-1979 (located in the 306-W building)
Thorium—cont. 

 Monitoring

• Very little data is available and can not be tied to operations at 

the site.

• There are only 11 in vitro bioassay (urinalysis) results for 

elemental thorium or Th-232 in the REX database in the July 

1972 through December 1983 period. There is one record in 

1979, seven in 1980, and three in 1981 (the years reflect the 

sample collection dates).

• The REX database contains 16 in vivo bioassay results for Th232 during the period under evaluation: one in 1972, one in 

1973, two in 1977, seven in 1979, and five in 1983. The four 

counts from 1972 through 1977 were whole body counts. All of 

the others were chest counts.
Uranium

 At the conclusion of SEC-00152, NIOSH’s research to 

that point indicated that very little HEU and 233U 

work was done after June 30, 1972

 Continued research at Hanford led NIOSH to follow 

a series of activities that were located in the 200 

and 300 areas involving HEU and 233U conducted 

after June 30, 1972
Uranium—cont. 

 These activities included

• Research by the Nuclear Experiments Group

• Defense-related metallurgical research at the 231Z, 

Plutonium Finishing Plant (234-5Z) and likely other 

facilities

• Research located in the 300 area including at the 325, 

303-C, 305, 313, 314, 324, 326, 327, and 333 buildings

• Criticality studies and associated fabrication of HEU for 

criticality studies in the 306 building
Uranium—cont. 

 Monitoring

• Hanford monitored workers for natural uranium exposure 

using total uranium (fluorimetric) and lung counting 

methods during this time period

• At the end of 1983 Hanford implemented and began to 

utilize methods for the determination of isotopic uranium 

in urine (alpha spectrometry)

• NIOSH has determined that it is unable to use natural 

uranium monitoring from this period to cover the types 

of work and research being conducted at Hanford during 

the proposed time period.
Conclusion from Research

 NIOSH has evaluated the available information 

and determined that it does not have access to 

sufficient personnel monitoring, workplace 

monitoring, or source-term data to sufficiently 

estimate potential internal exposures to HEU, U233, thorium, or neptunium during the period 

from July 1, 1972 through December 31, 1983.
Hanford SEC Petition 201

 Why the class?

• Workers were potentially exposed to thorium, neptunium, 

highly enriched uranium and 233U who were not monitored nor 

does a suitable dose reconstruction method exist.

• Several infeasibilities exist during the timeframe in question, 

and are presented in the form which provides broad coverage 

to the infeasibility (thorium, neptunium, highly enriched 

uranium, and 233U).

• Decision was based on lack of adequate biological monitoring 

data, sufficient air monitoring information, and/or sufficient 

process and radiological source-term data to reconstruct dose 

with sufficient accuracy.
Hanford SEC Petition 201—cont. 

 Why everyone?

• Based on dose reconstruction experience and records, 

NIOSH further determined that there is not sufficient 

information available to enable NIOSH to accurately 

assess whether an energy employee, or class of 

employees, did, or did not, potentially enter specific 

areas of Hanford during the time periods associated with 

Petition 201.
Hanford SEC Petition 201—cont. 

 What about employees not included in the SEC?

• NIOSH intends to use any internal and external 

monitoring data, and medical doses that may become 

available for an individual claim (and that can be 

interpreted using existing dose reconstruction processes 

or procedures). Therefore, dose reconstructions for 

individuals employed at the Hanford site during the 

period from July 1, 1972 through December 31, 1983, but 

who do not qualify for inclusion in the Special Exposure 

Cohort, may be performed using these data as 

appropriate.
Health Endangerment

 The evidence reviewed in this evaluation 

indicates that some workers in the class may 

have accumulated chronic radiation exposures 

through intakes of radionuclides and direct 

exposure to radioactive materials.

 Consequently, NIOSH is specifying that health 

may have been endangered for those workers 

covered by this evaluation who were employed 

for a number of work days aggregating at least 

250 work days within the parameters 

established for this class or in combination with 

work days within the parameters established for 

one or more other classes of employees in the 

SEC. 
Proposed Class

All employees of the Department of Energy, its 

predecessor agencies, and its contractors and 

subcontractors who worked at the Hanford site 

in Richland, Washington, from July 1, 1972 

through December 31, 1983, 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.
Potential Impact of SEC 

(Current Cases) 

 Total number of Hanford and PNNL cases: 4479

 Number withdrawn (SEC): 865

 Total number with a DR (at DOL): 3958

 Total number claims with employment in 

proposed class:

• Number of claims with presumptive cancer during the 

proposed SEC: 1522

• Number of claims with non-presumptive cancer 

during the proposed SEC: 1082

• Number of claims at NIOSH with a presumptive cancer: 59
Recommendation

 For the period July 1, 1972 through December 31, 

1983, NIOSH finds that radiation dose estimates 

cannot be reconstructed for compensation 

purposes

Class Feasibility Health Endangerment

July 1, 1972 –

December 31, 1983 No Yes