SC&A Site Profile and SEC Updates: 

Area IV, Santa Susana Field 

Laboratory (SSFL)

John Stiver, CHP

Health Physicist and Program Manager

S. Cohen and Associates

Contractor to: Advisory Board on Radiation Worker Health/ABRWH

Centers For Disease Control and Prevention

November 6, 2014

Los Angeles, California
Background

• 2006-2007: NIOSH first issued the six-volume TBD comprising the SSFL 

site profile (ORAUT-TKBS-0038)

• January 19 – April 20 2006: Series of 5 worker outreach meetings

• June 22, 2007: SEC Petition 00093 received 

– October 19, 2007: Petition qualified

– February 20, 2008: Evaluation report sent to the Advisory Board

– Petition discussed by Board – April 8 and June 26, 2008

• August 16, 2008: SC&A submits review of SSFL site profile

– Unique in that site profile review was conducted in midst of an ongoing SEC petition 

process

– total of 39 findings identified (many were different aspects of a single issue)

• TBD 1 (Introduction) - 2 findings

• TBD 2 (Site Description) – 6 findings

• TBD 3 (Medical Dose) - 2 findings

• TBD 4 (Environmental Dose) – 6 findings

• TBD 5 (Internal Dose) - 16 findings

• TBD 6 (external dose) - 7 findings

2
Background, Continued

• August 26, 2008: First SSFL Work Group meeting

– All site profile findings discussed but NONE closed

• Ongoing SEC deliberations

• Need for petitioners review and comment

• Discussed in terms of potential SEC impact

• Findings determined to be site profile issues pended

– Work group agreed that SC&A should combine closely related 

findings and produce a new SEC issues matrix

• April 17 2009: Second Work Group meeting

– New SC&A SEC issues matrix with total of 13 findings

• A mix of petitioner concerns, issues identified by NIOSH and combined SC&A findings

• This is the matrix that we are currently working from

– Discussions resulted in NIOSH being tasked with several action items for 

next meeting , which was held on April 20, 2010.

3
Background, Continued

• A lot of SEC activity took place in the intervening year 

between the 4/2009 and 4/2010 WG meetings 

– April 28 , 2009 - SEC 00093 - ER revised

– May 19, 2009 – SEC 00093: Board recommends a class be 

added to the SEC (January 1, 1955 – December 31, 1958)

• Effective date July 18 2009 

– SEC Petition 00156

• November 27, 2009: petition received and qualified

• January 15, 2010: Evaluation report sent to the Advisory Board

• Petition discussed by Board – February 9, 2010

• March 5, 2010: Board recommends a class be added to the SEC (January 1, 

1959 – December 31, 1964)

• Effective date May 5, 2010 

– Combined SECs 00093 and 00156 cover the period January 1, 

1955 – December 31, 1964

• Outstanding SEC issues may impact 1964 end date

4
Background, Continued

• April 20, 2010: Third Work Group meeting

– Discussed 13 SEC issues in context of NIOSH action items from April 2009

– SC&A presented a review of ORAUT-OTIB-0077, Rev. 00, External Coworker 

Dosimetry Data, August 2009

• 5 issues regarding the appropriateness of the “Boice” database for coworker 

modeling

– NIOSH Tasking

• Complete external dose coworker model including a report on approach to 

neutron dosimetry

• Complete an internal dose coworker model

• Provide updates to environmental TBD methods

– SC&A Tasking – Review the NIOSH work products as they are made available

• June 14, 2010: NIOSH releases white paper on neutron dosimetry 

“Neutron Exposures at Area IV of the Santa Susana Field Laboratory and 

Related Sites”

• October 2010 – SC&A nears completion on review of NIOSH white paper 

on neutron dosimetry 

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Current Status and Concerns

• Fast Forward to 2014

– No SC&A or Work Group activity since 2010

• March 14, 2014: NIOSH releases ORAUT-OTIB-0080 Rev 0. Internal 

Coworker Dosimetry Data for Area IV of the Santa Susana Field 

Laboratory and the DeSoto Avenue Facility

– Uses Boeing database (Boice data set abandoned)

– SC&A commences review in July 2014

• SSFL discussed briefly at April 2014 and July 2014 Board meetings

• October 16, 2014: Fourth WG meeting (teleconference)

– NIOSH update on forthcoming work products 

• New revision of ORAUT-OTIB-0077 based on Boeing database

• Environmental TBD revisions

– Restart SEC finding resolution process

• Only 1 of 12 issues closed (start date for nuclear operations)

6
Current Status and Concerns

• Issues Matrix Status at close of October 16 2014 Meeting 

– The September 24, 2014, NIOSH update used in the meeting is posted on the 

DCAS website: http://www.cdc.gov/niosh/ocas/pdfs/abrwh/scarpts/sca-ssflsecim-r1.pdf

– 1 finding was closed 

• #9 - Which areas (Area IV, Canoga Park, De Soto, and Downey) should be considered in the SEC 

petition and when did operations begin at these facilities (coverage dates)?

– Research [Sapere and Boeing (2005)] indicates that pre-1955 activities consisted mainly of design and 

construction operation. Further, there is no indication that radiological operations took place before 

1954.

– Petition is for SSFL Area IV. Canoga Park, De Soto, and Downey have separate petitions

– 1 open combined finding depends on internal coworker model (ORAUT-OTIB- 0080, Rev 0)

• #10 Adequacy of the internal monitoring program, pre-and post-January 1, 1959 (SC&A Issue) – subsumes 5 sub-issues

– Incomplete bioassay dataset and insufficient correlation of bioassay data to specific radionuclides 

– Missing radionuclides

– Difficulties with uranium bioassay methods

– No internal coworker model or source term data

– Erroneous data interpretation 

7
Current Status and Concerns

• Issues Matrix Status, continued

– 4 open findings depend on review of revised external coworker 

model (ORAUT-OTIB-0077 Rev 1)

• #1: The 1959 Sodium Reactor Experiment (SRE) Incident and Release of Core 

Gases. (Petitioner Issue) (internal subsumed in SEC) 

– WG agreed that this is a probably a site profile issue

• #2 Radiation Badges: This issue was based on a Tiger Team report indicating 

“inadequate radiation badges.” (Petitioner Issue) 

– WG agreed that this is a site profile issue

• #7 Identification of workers with blank radiation exposure record sheets in 

their file (NIOSH issue)

• #13 Justification for assignment of external dose estimates is not provided, 

and there is no coworker model for external exposures (personnel records are 

also of concern). Subsumes 3 areas of concern

– No external coworker model

– Workers were unlikely to have been monitored for thermal neutrons

– Dosimeter response to low-energy photons

8
Current Status and Concerns

• Issues Matrix Status, continued

– 4 open findings depend on revisions to internal AND external 

coworker model

• #4 - Uranium Fires: The petitioner refers to numerous uranium fires, cites two 

incidents of a sodium explosion, and expresses concern that monitoring was 

lacking regarding facility incidents. (Petitioner Issue)

• #6 - The Sodium Disposal Facility (also known as the Sodium Burn Pit): This 

facility was not adequately monitored and/or records are missing. (Petitioner 

Issue

• #8 - Monitoring of firemen from other sites who were involved with fires or 

other events at SSFL (NIOSH issue)

• #11 - Lack of information related to the potential exposures associated with 

facility “incidents” ( some overlap with Sodium Reactor Experiment and 

Sodium Burn Pit).

9
Current Status and Concerns

• 3 open findings Depend on Revisions to Environmental TBD

– #3 Tritium Plumes: Workers may have been exposed to drinking 

water contaminated with tritium. (Petitioner Issue) 

– #5 Air Monitoring: The petitioner maintains that air monitoring was 

insufficient. (Petitioner Issue)

– #12 Lack of information on environmental exposures (SC&A Issue)

• Combined finding that subsumes 2 issues

– Back extrapolation of stack emission data: The surrogate use of the time-integrated 

average yearly gross alpha/gross beta stack emissions corresponding to years 1971 

to 1999 (when stack measurements were taken) is likely to underestimate stack 

emissions for years 1954 through 1970

– Contaminated groundwater impacting onsite drinking water supplies (some 

overlap with #3 above)

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Current Status and Concerns 

(continued)

• Status of SC&A Activities

– SC&A review of June 2010 NIOSH white paper on n/p ratios submitted 

to the work group on October 23, 2014

– Nearing completion on review of ORAUT-OTIB-0080 Rev 0 (late 

November 2014)

– Awaiting release of ORAUT-OTIB-0077 Rev 1 (External coworker 

model)

– Awaiting release of Environmental TBD updates

– Resolution of open SEC issues contingent on completion of all three 

reviews

• Next WG meeting on/about January 9, 2015

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Questions?

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