SC&A’s Review of Rocky Flats Plant 

Technical Basis Document Revisions and 

Issues

Joe Fitzgerald, MS, MPH, Lead Reviewer

Ron Buchanan, PhD, CHP

Advisory Board on Radiation and Worker Health, Rocky 

Flats Plant Work Group

October 4, 2022
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SC&A’s review of RFP revised TBDs

 SC&A evaluated the latest revised Rocky Flats Plant (RFP) 

technical basis documents (TBDs) for resolution of findings and 

observations identified in SC&A’s 2005 site profile review 

 SC&A’s December 3, 2021, evaluation report addressed:

– Resolved issues: SC&A’s 2005 findings and observations resolved by 

revisions to the RFP TBDs and for which closure by the work group is 

recommended

– Unresolved issues: SC&A’s 2005 findings and observations that 

remain to be addressed by NIOSH

– New issues: Arising from SC&A’s 2021 review of the revised TBDs

 NIOSH responded to SC&A’s 2021 review on July 22, 2022
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SC&A’s issues for TBD-2, “Site Description,” 

resolved by revised TBDs

 SC&A finds that all previous TBD-2 issues have been addressed in rev. 02

 Rev. 02 is more comprehensive in scope and depth and includes more details 

on site closure and decommissioning (SC&A’s observation 1), as well as 

information about specific operations and their operational timelines, including 

recycled uranium and uranium-233 (SC&A’s observation 2) 

 SC&A recommends closure of finding 8 (inadequate information about recycled 

uranium), based on updated treatment of the issue in the internal dose TBD-5

 SC&A recommends that TBD-2 be revised to be consistent with TBD-5

 NIOSH plans to address this recommendation in future TBD revisions 

 SC&A concurs with NIOSH’s response and plans to review such future revisions
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SC&A’s issues for TBD-3, “Occupational 

Medical Dose,” resolved by TBD revision

 TBD-3 finding 5 was about radiation exposure from occupationally 

necessitated medical x-ray

 SC&A finds all remaining issues for finding 5 have been addressed 

and resolved in rev. 03 of TBD-3 and recommends closure

 General review of rev. 03 did not identify any new findings

 New issue: SC&A identified some incorrect tables listed on page 2 

of the revised TBD-3

– NIOSH plans to address these errors in future TBD revisions

– SC&A concurs with NIOSH’s response and plans to review such future 

revisions
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SC&A’s finding 9 for TBD-4, “Environmental 

Dose,” resolved by TBD revision

 TBD-4 finding 9 was about inadequacies in addressing 

potential environmental exposure from routine and ambient 

airborne releases and resuspension of contaminated soil

 SC&A finds that rev. 03 of TBD-4 resolves finding 9:

– NIOSH has provided better justification of its basis in available site 

monitoring data

– NIOSH has added more specific information and guidance about the 

contribution of resuspension of soil contaminants for occupational 

environmental exposures

 SC&A recommends closure of this finding
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SC&A’s other issues for TBD-4 resolved by TBD 

revision

 SC&A found rev. 03 of TBD-4 addresses other remaining 

issues:

– Observation 3: Use of the RATCHET air dispersion model

– Consideration of potential environmental dose reconstruction issues 

stemming from the 1989 FBI investigation

 SC&A recommends closure of these issues
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SC&A’s findings 1 and 2 for TBD-5, “Occupational 

Internal Dose,” resolved by TBD revision

Finding 1

 TBD-5 finding 1 was that 

NIOSH’s suggested use of 

urine bioassay minimum 

detectable amount (MDA) 

values appears low

 SC&A finds that TBD-5 

rev. 03 resolves this issue 

and recommends closure

Finding 2

 TBD-5 finding 2 was that the 

TBD lacks definitive direction 

in some instances

 SC&A finds that TBD-5 

rev. 03 resolves this issue 

and recommends closure
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New SC&A TBD-5 issue about MDA units

 SC&A finds that table B-11, page 104, lacks units for the 

minimum detectable amount (MDA) values for americium-241; 

it appears that it should specify the unit of nanocuries

 NIOSH plans to edit TBD-5 to add units for MDA values 

 SC&A concurs with NIOSH’s response and will review the 

revised TBD-5 when available
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SC&A’s finding 7 for TBD-5 resolved by TBD 

revision

 TBD-5 finding 7 was that TBD-5 should include recommendations 

for ingestion intakes or direct reference to the appropriate ingestionintake-related document.

 NIOSH response:

– TBDs are designed to contain site-specific guidance. The selection of intake 

pathway is a generic issue to all sites and is therefore covered in ORAUTOTIB-0060, “Internal Dose Reconstruction” (2018). 

– There is no site-specific scenario identified in this finding that would warrant 

the TBD to provide site-specific guidance. Therefore, no changes to TBD-5 

are recommended.

 SC&A accepts NIOSH’s clarification and recommends closure of 

TBD-5 finding 7.
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SC&A’s observation 4 for TBD-5 about wound 

dose model resolved

 SC&A’s observation 4 noted that while the approach in TBD-5 

is claimant favorable for cited organs, a more claimantfavorable approach for lymph nodes and skin cancers may be 

available in the 2003 model by Guilmette and Durbin

 NIOSH noted in the revised TBD that guidance in ORAUTOTIB-0022 references this model

 NIOSH’s response satisfied SC&A’s observation
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SC&A’s finding 3 for TBD-6, “Occupational 

External Dose,” resolved by TBD revision

 TBD-6 finding 3 was concerned with the interpretation of NTA 

film data for workers who were not included in the NDRP

 Rev. 03 of TBD-6 addresses this finding by use of neutron-tophoton ratios, coupled with use of available coexposure data

 SC&A recommends closure of this finding
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SC&A’s finding 4 for TBD-6 resolved by TBD 

revision

 TBD-6 finding 4 was concerned with treatment of personal 

dosimeter placement and angular dependence

 Rev. 03 of TBD-6 addresses this finding by analysis of angular 

dependence of the monitoring devices

 SC&A recommends closure of this finding
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SC&A’s finding 6 for TBD-6 resolved by TBD 

revision

 TBD-6 finding 6 was concerned with potential calibration 

errors, technology deficiencies, and possible data integrity 

issues that could have contributed to missed dose

 Rev. 03 of TBD-6 addresses these issues

 SC&A recommends closure of this finding
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SC&A’s finding 10 for TBD-6 resolved by TBD 

revision

 TBD-6 finding 10 was concerned with hand and wrist doses

 Rev. 03 of TBD-6 addresses these extremity doses

 SC&A recommends closure of this finding
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SC&A’s finding 11 for TBD-6 resolved by TBD 

revision

 TBD-6 finding 11 was concerned with the potentially significant 

doses from industrial x-ray and neutron generators used for 

research and development and nondestructive work

 Rev. 03 of TBD-6 addresses these issues

 SC&A recommends closure of this finding
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New SC&A issue about neutron dose factors in 

TBD-6

 SC&A observes that NIOSH needs to clarify the reason for the 

change in neutron dose multiplier factors listed in table 6-16 of 

TBD-6 rev. 03 compared to table 6-14 of rev. 00

 NIOSH responded that these multiplier factors were updated 

based on guidance in ORAUT-OTIB-0055 (2006), which was 

issued after TBD-6 rev. 00 (2004)

 SC&A concurs with NIOSH’s response and recommends 

closure
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New SC&A issue about neutron LOD values in 

TBD-6

 SC&A observes that the reason for recommending a limit of 

detection (LOD) value of 226 millirem (mrem) in table 6-18 and 

table 6-19 needs clarification

 NIOSH response for LOD equation for 1962 and 1963:

– LOD = Blank + 1.65 × sqrt(Blank)

– Value of “Blank” is calculated by the equation Blank = 100 × (16/10), which 

results in 160 mrem

– Therefore, LOD value should be 160 + 1.65 × sqrt(160) or 181 mrem (instead 

of 226 mrem)

 NIOSH will correct the LOD value for 1962 and 1963 in table 6-18 in 

future revisions to TBD-6

 SC&A concurs with NIOSH’s response and will review future 

revisions
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New SC&A issue about references for LOD 

values in TBD-6

 SC&A observes that references for recommended photon, 

neutron, and beta LOD values for 2004 and 2005 are needed

 NIOSH responded that future TBD-6 revisions will provide 

references for the LOD values for 2004 and 2005

 SC&A concurs with NIOSH’s response and will review the 

revision when available
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New SC&A editorial items about missing or 

incorrect references in TBD-6

 SC&A finds that the following references were used in the text but 

were not listed in the reference section on pages 64–69:

– Page 10: Sebelius (2013)

– Page 11: NIOSH (2013)

– Page 94: NIOSH (2006)

 The caption for table C-8 given in the list of tables at the bottom of 

page 93 should use the phrase “uranium workers,” not “plutonium 

workers”

 NIOSH indicates that future revisions of TBD-6 will correct the 

references and fix the caption for table C-8

 SC&A concurs with NIOSH’s response and will review the revision 

when available
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Summary of SC&A’s review of RFP TBD 

revisions and issues

 SC&A found that the revised TBDs addressed most (but not all) 

of SC&A’s 2005 findings and observations about the original 

TBD

 SC&A found that NIOSH addressed some of the other open 

issues from SC&A’s December 2021 review of the RFP TBDs 

in its July 2022 response to SC&A’s December 2021 review 

and recommends closure as noted in this presentation

 SC&A concurs with NIOSH’s responses on remaining items 

and will review changes made in future revised TBDs when 

available
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Questions?