DISCLAIMER: This is a working document provided by the Centers for Disease Control and Prevention (CDC) 

technical support contractor, SC&A for use in discussions with the National Institute for Occupational Safety and 

Health (NIOSH) and the Advisory Board on Radiation and Worker Health (ABRWH), including its Working Groups or 

Subcommittees. Documents produced by SC&A, such as memorandum, white paper, draft or working documents are 

not final NIOSH or ABRWH products or positions, unless specifically marked as such. This document prepared by 

SC&A represents its preliminary evaluation on technical issues.

NOTICE: This document has been reviewed to identify and redact any information that is protected by the 

Privacy Act 5 U.S.C. § 552a and has been cleared for distribution. 

Memorandum

To: SRS Work Group and SEC Issues Work Group

From: SC&A, Inc.

Date: April 21, 2022 

Subject: SRS Trivalent Bioassay Variability Status and Recommendation

Background

During the 1970s and 1980s, the Savannah River Site (SRS) performed bioassay analysis for 

trivalent actinides—americium/curium/californium (Am/Cm/Cf)—for routine internal 

monitoring and radionuclide intake confirmation and evaluation. These bioassay measurements 

are captured in laboratory logbooks that demonstrate that SRS often split a single urine voiding 

into multiple discs or aliquots, which were measured separately and averaged to obtain a 

reported result. The National Institute for Occupational Safety and Health (NIOSH) used the 

laboratory logbooks and the individual aliquot measurements in the construction of its 

co-exposure model as documented in ORAUT-OTIB-0081, revision 05, “Internal Coworker 

Dosimetry Data for the Savannah River Site” (NIOSH, 2020a; “OTIB-0081”).1 

1 As discussed later in this report, NIOSH is currently in the process of revising OTIB-0081 to include a recoding 

of all trivalent bioassay data as well as a statistical analysis of variability.

NIOSH’s guiding documentation for the formulation and evaluation of co-exposure modeling is 

in DCAS-IG-006, revision 00, “Criteria for the Evaluation and Use of Co-Exposure Datasets” 

(NIOSH, 2020b; “IG-006”). One of the four tenets described in IG-006 is the concept of “data 

adequacy,” the general evaluation of which is described as follows: 

The measurement techniques employed must be evaluated to ensure that they are 

capable of quantitatively measuring the exposure of interest. [NIOSH, 2020b, 

p. 5] 

IG-006 further states: 

The quality of the available data also needs to be considered. This would include 

a review of the appropriate collection and analysis of blank samples. When paired 

measurements are available, the precision between measurements should be 

examined. If widely different results from the same aliquot are observed, the 

effect this might have on the usefulness of the data should be considered. 

[NIOSH, 2020b, p. 6; emphasis added] 
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SC&A first expressed concern about the issue of observed variability among multiple aliquots of 

the trivalent bioassay samples at SRS as far back as February 2014 (SC&A, 2014, pp. 6–31; SRS 

WG, 2014, pp. 186–198). The issue of data adequacy and variability was discussed in multiple 

meetings of the Special Exposure Cohort (SEC) Issues work group (WG) (SEC WG, 2014a, 

pp. 11, 14; 2014b, p. 18; 2015, p. 72) and by the joint SRS and SEC Issues WGs (SRS WG & 

SEC WG, 2017, p. 110, 113; 2019, p. 12). Additionally, the issue of observed variability of 

multiple aliquot measurements was discussed in attachment D of OTIB-0081, which documents

the overall SRS co-exposure model (NIOSH, 2020a, pp. 159–163), and in SC&A’s review of the 

prior revision of that document (SC&A, 2020a, pp. 15–20).

Most Recent Document Exchanges and Work Group Discussion

The most recent pertinent technical documents were issued in 2020 and involved an SC&A 

memorandum to describe the current status of the issue and a NIOSH response to SC&A’s 

memorandum:

• SC&A (2020b): “Summary Position on Trivalent Bioassay Variability”

• NIOSH (2020c): “Response to SC&A Memorandum, ‘Summary Position on Trivalent 

Bioassay Variability’”

Each of these document’s conclusions are briefly summarized in the next two paragraphs, 

respectively. 

SC&A (2020b) concluded that the observed variability in trivalent actinide bioassay samples had 

not been sufficiently explained to justify its use in either individual dose reconstruction or 

co-exposure formulation. This conclusion was based on SC&A’s interpretation of the IG-006 

co-exposure guidelines concerning data adequacy as summarized in the background section of 

this memorandum. SC&A found that the observed variability in selected examples fell outside of 

the precision reported in a 1987 SRS procedure (SRS, 1987, pp. 60–65). More importantly, 

SC&A determined that pertinent information to correctly interpret and validate the SRS trivalent 

bioassay data was lacking. Such information includes laboratory benchtop procedures, 

documented quality assurance tests, prospective acceptance criteria for blanks/spikes, and formal 

laboratory calculations with clear indications of necessary terms (volume, counting efficiency, 

chemical yield, measurement uncertainty). SC&A also indicated that, while formal 

documentation may be lacking, interviews with subject-matter experts may also provide useful 

information to understand and interpret the available trivalent actinide data. Finally, SC&A did 

not accept NIOSH’s contention that the averaging mechanisms of the co-exposure process 

obviate the observed variability and data adequacy concerns.

NIOSH’s (2020c) response noted that the examples provided by SC&A were selective and that 

the determinations of acceptable variability were ultimately subjective. NIOSH reasoned that 

there are realistic situations in which a given sample might display subjectively high variability 

without calling into question the analysis method. In particular, NIOSH offered an example

involving a suspected uptake of radioactive material in which the efficiency, rather than the 

precision, of the analysis is of more import to quickly identify and treat the individual (e.g.,

through administration of chelating agents). NIOSH also asserted that there is no real criterion

for acceptable variability among sample aliquots even by contemporary radiochemical laboratory 
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standards. NIOSH proposed that a more rigorous statistical metric of variation, such as the 

coefficient of variation (COV), is more appropriate in evaluating the variation among aliquots. 

Regarding the availability of documentation about specific processing activities of the SRS 

bioassay laboratory, NIOSH noted that such documentation is certainly desirable but generally 

unavailable for capture and interpretation, particularly before the advent of the U.S. Department 

of Energy Laboratory Accreditation Program (DOELAP). NIOSH commented that the bioassay 

logbooks themselves had evidence of blanks/spikes being used. In addition to the blanks/spikes, 

it was apparent that SRS personnel had reviewed and signed off on these logbooks, which 

provides weight of evidence as to the data’s veracity. NIOSH concluded that absent contradicting 

information (e.g., evidence of falsification, records destruction, typographical database errors), 

the “fitness of the analytical results for the original intended purpose implies fitness for use in 

dose reconstructions in a compensation program” (NIOSH, 2020c, p. 8). 

These two previous technical documents were presented and discussed at the joint meeting of the 

SRS and SEC Issues WGs on November 20, 2020. As a result of those discussions, the WGs

tasked SC&A and NIOSH with the following two actions (SRS WG & SEC WG, 2020, pp. 132–

135): 

1. SC&A is to develop a set of specific technical questions and provide those questions to 

NIOSH in preparation for a technical call to be held between NIOSH, SC&A, and WG

members (as available).

2. NIOSH is to complete its recoding effort for the trivalent actinide bioassay data, which 

includes a detailed review by a health physicist prior to completion. NIOSH will then 

provide updated co-exposure estimates along with an analysis of the COV as 

recommended in NIOSH (2020c). SC&A is to review the COV analysis when available.

The next section describes the progress made on action item 1. As of this writing, action item 2 is 

still in progress with NIOSH, who are revising OTIB-0081 to include the recoded trivalent 

actinide data and an analysis of the COV for the entire dataset (the upcoming revision will be 

revision 06 of OTIB-0081).

Progress and Status of Action Item 1 

SC&A delivered a set of technical questions to NIOSH on January 5, 2021, and held a technical 

call on January 28, 2021, to address the submitted questions. The list of SC&A’s original 

questions and SC&A’s meeting minutes of the technical call2

2 SC&A submitted meeting minutes to NIOSH on January 29, 2021, for comment and modification (as needed), 

which resulted in a followup email from NIOSH that gave additional information and Site Research Database 

(SRDB) references that were germane to the additional information sought by SC&A. 

 are included for reference in 

attachments A and B, respectively. After that technical call, NIOSH provided SC&A with some 

example SRDB reference numbers that may contain the type of information sought to resolve 

concerns over data adequacy. NIOSH also indicated that there may be other such examples in the 

SRDB. Unfortunately, SC&A is still unable to access the SRDB due to access restrictions 

imposed by the cybersecurity modernization initiative. However, the original SRDB references

indicated by NIOSH in February 2021 were made available to SC&A in January 2022 via the 
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new secure access module called the NIOSH Edge Computing Platform. The following list 

briefly summarizes the supplied SRDB file contents and relevance:

• Dupont Savannah River Operating List (DPSOL) 47-206, revision 1, “AmericiumCurium-Californium, Plutonium, Neptunium, Enriched Uranium Sequential 

Determinations” (SRS, 1987): This DPSOL was also reviewed for SC&A’s (2020b) 

memorandum to the WG. This document provides generic information, such as the 

minimum detectable activity (MDA) and the estimated precision at the 95th percentile 

confidence level. 

• Dupont Standard Operating Procedure (DPSOP) 47, revision 28, “Radiobioassay 

Laboratory Procedures” (SRS, 1991): Contains updated generic procedures with various 

dates between 1986 and 1991. This DPSOP also contains duplicate versions of the 

previous record (as DPSOP 47-206, rev. 1). Documentation indicates that the transuranic 

bioassay analysis procedure had been integrated into Health Physics (HP) Manual 5Q2.3. 

• OSR 4-257, “Sample Counting Data Sheet” (SRS, 1977): This SRDB file contains 

hundreds of examples of filled-out sample counting data sheets (Form OSR 4-257), 

which collect bioassay-specific information such as counting times, sample number, 

logbook reference, total counts, background counts, disintegrations per minute (dpm) per 

disc, conversion factors, dpm per liter, and a remarks column. While many of the 

example counting sheets do not specify a year, it is likely that they are from 1977, based 

on other dated documents in the file. 

• OSR 4-298, “Health Physics Bioassay Tritium Data (Receiving Report) (Computer 

Document)” (SRS, 1980): This SRDB file contains hundreds of tritium bioassay 

logsheets from 1980. The logsheets have fields for the following entries: roll code, roll 

prefix, employee number, date (month and day), result (microcuries per liter), area, 

department, employee name, sample counts, and a checkbox to indicate whether the 

sample was routine or special. 

While informative, SC&A does not find that these standard procedures and example counting 

sheets necessarily provide the sought-after details on actual laboratory procedures at the 

benchtop level. 

Additionally, NIOSH indicated that other examples may exist at SRS itself that have not been 

captured and provided some potential “box” descriptions of hardcopy records that include 

information such as: 

• Counting room daily reports 

• Counting room source checks 

• Alpha spectrometry raw data

• Tritium quality control (QC) data 

• Gamma spectrometry 

• Plutonium alpha spectrometry data

• Enriched uranium alpha spectrometry data 
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However, SC&A notes that many of the resources in this list refer to the spectrometric analysis 

method, which was not used at SRS during the period of interest (before 1990), and that routine 

samples were not analyzed via spectrometry until 1995 (NIOSH, 2019, p. 41). 

Status and Path Forward

Based on the technical call and additional SRDB documents supplied by NIOSH, it is apparent to 

SC&A that while examples exist of the types of laboratory quality assurance (QA) and process 

specific information (inclusion of blanks and efficiency documentation) requested, actual 

benchtop procedures of the type of specificity that SC&A was seeking have not yet been located. 

Additionally, it is somewhat questionable whether that type of information would still be 

available. As noted by NIOSH (2020c, p. 6): 

Locating and vetting radiobioassay analytical results for a facility is in itself a 

difficult task. Locating all relevant procedures and QA records for those results is 

usually not feasible, especially in the pre-DOELAP era (i.e., before 1996). 

SC&A (2020b) had also indicated that a second potential source of information would be to seek 

out interview subjects who may have first-hand knowledge of the laboratory operations during 

the pre-1990 time period. While it is always helpful to speak to former workers with specific 

experience, NIOSH (2020c) noted another potential pitfall in its response:

Considerable subject matter knowledge would be required to properly interpret 

procedures and QA records (especially for pre-DOELAP analyses) in any effort to 

verify what the cognizant technical authority (e.g., the radiochemist) approved at 

the time of the analysis (as indicated by his/her signature). [NIOSH, 2020c, p. 6] 

Nonetheless, SC&A was able to examine the claimant population for potential interview subjects 

before the cybersecurity modernization initiative and located 11 individuals who indicated some 

experience working in the bioassay laboratory. Attachment C briefly summarizes these 11 

individuals. However, SC&A notes that few of these individuals appear to qualify as the type of 

high-level radiochemist who would bring the necessary expertise to answer some of SC&A’s 

very specific laboratory process questions. 

Finally, SC&A notes that NIOSH is in the process of recoding all of the trivalent americium data 

from the hardcopy logbook data with a focused review of each datapoint by knowledgeable 

NIOSH health physicists. As part of that effort, NIOSH has committed to performing a rigorous 

statistical evaluation of the COV, which will likely significantly inform future discussions. As 

this new material has not yet been finalized, SC&A is not in a position to comment on its

conclusions. However, SC&A believes this statistical avenue to likely be the most fruitful in 

resolving the ongoing data adequacy concerns about the trivalent bioassay data.
SC&A, Inc.

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References

National Institute for Occupational Safety and Health. (2020a). Internal coworker dosimetry data 

for the Savannah River Site (ORAUT-OTIB-0081, rev. 05).

https://www.cdc.gov/niosh/ocas/pdfs/tibs/or-t81-r5-508.pdf 

National Institute for Occupational Safety and Health. (2020b). Criteria for the evaluation and 

use of co-exposure datasets (DCAS-IG-006, rev. 00). 

https://www.cdc.gov/niosh/ocas/pdfs/dr/dc-ig-006-r0-508.pdf

National Institute for Occupational Safety and Health. (2020c). Response to SC&A 

memorandum, “Summary position on trivalent bioassay variability” [Response paper]. 

https://ftp.cdc.gov/pub/FOIAREQ/183766-508.pdf 

Savannah River Site. (1977). Counting room sample counts [SRDB file containing multiple 

filled-out copies of Form OSR 4-257, “Sample counting data sheet”]. SRDB Ref. ID 53258, 

pp. 38–592 

Savannah River Site. (1980). Bioassay receiving report, 1980, tritium [SRDB file containing 

multiple filled-out copies of Form OSR 4-298, rev. 4-73, “Health physics – Bioassay tritium data 

(receiving report) (computer document)”]. SRDB Ref. ID 153989 

Savannah River Site. (1987). Americium-curium-californium, plutonium, neptunium, enriched 

uranium sequential determinations (DPSOL 47-206, rev. 1). SRDB Ref. ID 45029, PDF pp. 60–

65 

Savannah River Site. (1991). Radiobioassay laboratory procedures (DPSOP 47, rev. 28). SRDB 

Ref. ID 45959 

Savannah River Site Work Group. (2014). Advisory Board on Radiation and Worker Health, 

Savannah River Site Work Group, Wednesday February 26, 2014 [Transcript of teleconference 

meeting]. https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2014/wgtr022614.pdf

Savannah River Site Work Group & SEC Issues Work Group. (2017). Joint meeting of the 

Savannah River Site (SRS) Work Group and the Special Exposure Cohort (SEC) Issues Work 

Group, Wednesday, August 16, 2017 [Transcript of teleconference meeting]. 

https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2017/wgtr081617-508.pdf

Savannah River Site Work Group & SEC Issues Work Group. (2019). Savannah River Site (SRS) 

and SEC Issues Work Groups joint meeting Thursday, December 5, 2019 [Transcript]. 

https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2019/wgtr120519-508.pdf

Savannah River Site WG & SEC Issues WG. (2020). Savannah River Site (SRS) and SEC Issues 

Work Groups joint meeting Friday, November 20, 2020 [Transcript of teleconference meeting].

https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2020/wgtr112020-508.pdf
SC&A, Inc.

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NOTICE: This document has been reviewed to identify and redact any information that is protected by the 

Privacy Act 5 U.S.C. § 552a and has been cleared for distribution. 

SC&A, Inc. (2014, February 24). Discussion items and clarifications for February 26th work 

group meeting [Memorandum]. https://www.cdc.gov/niosh/ocas/pdfs/abrwh/scarpts/sca-srswg022414.pdf

SC&A, Inc. (2020a). Review of ORAUT-OTIB-0081, revision 04, “Internal coworker dosimetry 

data for the Savannah River Site” (SCA-TR-2019-SEC004, rev. 1). 

https://ftp.cdc.gov/pub/FOIAREQ/181746_red-508.pdf 

SC&A, Inc. (2020b, June 3). Summary position on trivalent bioassay variability [Memorandum]. 

https://ftp.cdc.gov/pub/FOIAREQ/181759-508.pdf 

SEC Issues Work Group. (2014a). Monday July 28, 2014 [Transcript]. 

https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2014/wgtr072814.pdf

SEC Issues Work Group. (2014b). Tuesday October 28, 2014 [Transcript of teleconference 

meeting]. https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2014/wgtr102814.pdf 

SEC Issues Work Group. (2015). Tuesday March 10, 2015 [Transcript of teleconference 

meeting]. https://www.cdc.gov/niosh/ocas/pdfs/abrwh/2015/wgtr031015.pdf 
SC&A, Inc.

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Attachment A: SC&A’s Clarifying Technical Questions Transmitted to NIOSH on 

January 5, 2021

In general, SC&A is less concerned about what was done for each individual measurement (i.e., 

validating each datapoint) and more concerned with the overall process. To try to illustrate this, 

please consider the following simplified example:

SRS identified that urine samples would be processed in accordance with “Procedure X,” 

counted on “Counter Y,” and calculated in accordance with “Procedure Z,” and that X, Y, and Z 

contained the pertinent technical details:

• Did Procedure X state the use of reagents at specific concentrations and volumes, 

including tracers, spiked and blanks samples, without regard for using 6N HNO3 versus 

8N, or 1 spike per day versus 1 spike per batch of 20? 

• Did the procedure for Counter Y require a determination of measurement efficiency 

(cpm/dpm) and was it required to check this, without regard for what the efficiency value 

was or how often it was checked?

• Did Procedure Z specify how to derive the final values, including the assigned chemical 

recovery for each batch/sample/whatever, dilution factors without regard for what the 

values were?

Specific Questions:

• Is there a record of what analytical procedures were used for chemical separation, 

radiometric assay (counting) and calculation over specific time periods? Examples:

– SRS laboratory procedures for chemical separations;

– Identification of the counters used; 

– Method for converting counting data into concentrations of target analyte per unit 

volume of urine for reporting (dpm/1.5L)

• Has the method of determining the efficiency of the analytical process (chemical 

separation, mounting, counting, etc.) been established? Examples: 

– How did the laboratory personnel know how much of the target analyte was identified 

in a sample such that the results could be correlated to the actual target analyte 

concentration in the sample?

– How did they account for losses during processing? 

– How was the detection efficiency (cpm/dpm) of the radiometric equipment 

determined?

• Are there records that indicate the process that SRS executed from start to finish? 

Examples: 

– Sample tracking; 

– Determination of appropriate volumes for specific purposes; 
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– Data review;

– Evaluation of sample results relative to predetermined acceptance criteria;

• Are there SRS laboratory personnel who processed these bioassay samples, and are we 

able to access them for some simple questions?
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Attachment B: SC&A’s Meeting Minutes from the Technical Call held 

January 28, 2021

NIOSH: The degree to which we can answer these questions is highly dependent on time period. 

In the late 1970s and 80s–90s, we have record of the specific laboratory analytical procedures. In 

the earlier time periods we don’t have the site-specific procedures. In the 1960s, we have largely 

the description of what they were doing at conference proceedings. You can infer that some of 

these things were being done. 

SC&A: I was not able to clearly correlate a procedure from SRS or otherwise with a time period. 

NIOSH: There are specific SRDBs (DPSOLs), one of which is 1991. 

NIOSH: SRDB 86192 contains some of the DPSOL 47 procedures. It talks about the sample 

counting data sheets. They entered the counter, how the logbooks were compiled. 

SC&A: Does that identify the actual type of counter? 

NIOSH: This particular procedure is used for Am/Cm/Cf, Pu etc. on how to fill out the sample 

data sheet. A lot of the early procedures used were published into peer reviewed journals. Then 

they got migrated into DPSOLs. Keep in mind, I mentioned the sample counting datasheets, we 

have examples in the SRDB. And there are examples of that datasheet going back to the 1960s. 

SC&A: The analytical procedures to determine the aliquot size, separation chemistry, chemical 

yield, mounting, counting, data reduction, etc., these are in the DPSOL procedures? 

NIOSH: When we get into the 1990s it’s not DPSOLs but it’s 5Q or something. 

NIOSH: Some of what we have are DuPont procedures that carried out into the Westinghouse 

era.

NIOSH: Going back from earlier than 1986 or so we don’t necessarily have the procedures, but 

they were documented in the peer reviewed journals. 

SC&A: So, we don’t have necessarily a benchtop procedure. 

NIOSH: I’m not sure if we have the rev. 01 version of these procedures. Also searching in 

EDWS—that’s where a lot of this information came from—I’m not sure we’ve gone into the 

level of detail that SC&A is looking for. I know that some of the datasheets that have efficiencies 

and such we have not captured. That does not mean that it doesn’t exist. I know there are boxes 

of sample counting sheets that are still on site. 

SC&A: On the second bullet . . . any sort of benchtop procedure will have losses due to chemical 

processing, so we’re trying to figure out how those were dealt with. I don’t have any doubt that 

the samples were processed with some basic sample chemistry (basic solubilities, aqueous versus 

organic fractions, etc.). How did they determine what the processing losses were and correct for 

them? Typically this is done with (chemical yield) tracers of stable carriers (not applicable for 

Am). How do you determine the measurement efficiency (cpm/dpm) of the counters? These are 
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the basic aspects of a radiochemical assay, really the two most important things with respect to 

the data reflecting reality. The key question is: Was there an acknowledgement of the importance 

of these aspects and is that captured in documents that were formalized, served as the basis for 

personnel training, and were maintained under some types of revision control? Essentially, was 

there a formal system of controls for all aspects of the analytical process? I’m less concerned 

about the details of the processing of each specific sample. 

NIOSH: What would you need to satisfy your question? We have the OTIB references, which 

describe an MDA. We have the logbooks that show they were regularly counting the blanks and 

spikes, subtract background, and efficiencies. There was evidence they were doing that. 

SC&A: There is certainly evidence those types of activities were occurring in general. But more 

specifically, was there a predetermined acceptance range for blanks and spiked samples? How 

were the measurement efficiencies established? What type of radiometric instruments were used? 

It was clearly not alpha spectrometry for the earlier assays. I agree there is inferential 

information out there—you can see that in the logbooks I looked at—there were typically a blank 

and spiked sample analyzed with most batches.

NIOSH: I don’t think I’ve seen a procedure that outlines everything that you’re talking about 

there. But in the EDWS there are boxes of data such as for QC data for tritium. Counting room 

source checks/Pu alpha spectrometry data . . . we have not yet captured any of that information. 

Some of it is likely still in hard copy. So it sounds like some of what you are looking for is that 

level of detail, but I’m not sure we have that. You may find examples of it, but not to the level 

you’re looking for. 

SC&A: If those kinds of things exist for the Am data, then that would certainly be helpful. 

NIOSH: What we do is when we need information, we go to the site and scan it and upload it to 

the SRDB. SRDB 53258 has plutonium information in it which may be helpful. 
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Attachment C: Potential Interview Subjects Identified in the Claimant Population

Case 

ID *

Approximate 

relevant 

employment 

period

Position title

Summary of relevant experience identified in the 

computer-aided telephone interview and/or 

Department of Labor case files

A Mid to late 

1980s

Laboratory 

Technician

[redacted]

B 1980s Laboratory 

Technician

[redacted]

C 1970s and 

1980s

Laboratory 

Technician

[redacted]

D 1970s and 

1980s

Chemist, Manager [redacted]

E 1970s and 

1980s

Supervisor, 

Laboratory 

Technician

[redacted]

F 1970s and 

1980s

Technical Assistant, 

Health Physics

[redacted]

G Late 1970s 

and early 

1980s

Laboratory 

Technician

[redacted]

H 1980s Clerk, Laboratory 

Technician

[redacted]

I Mid 1980s Laborer, Laboratory 

Technician

[redacted]

J 1980s Laboratory 

Technician, 

Technical Analyst

[redacted]

K 1970s and 

1980s

[redacted] [redacted]

* The “Case ID” is an arbitrary number assigned by SC&A to protect claimant privacy.