November 2, 2007
The Honorable A. J. Eggenberger
Defense Facilities Nuclear Safety Board
Dear Mr. Chairman:
The purpose of this letter is to report the results of the review of National Nuclear
Security Administration (NNSA) site office and contractor procedures and mechanisms
for using the 25 rem evaluation guideline (EG) as required under Deliverable 8.9.1 of the
Department of Energy's (DOE) Implementation Plan (IP) for Defense Nuclear Facilities
Safety Board (DNFSB) recommendation 2004-2, Active Confinement Systems.
Recommendation 2004-2, the Department's 2004-2 IP, and DNFSB/TECH-34,
Confinement of Radioactive Materials at Defense Nuclear Facilities, document concerns
that the 25 rem site boundary exposure EG is not being solely used for classification of
safety controls as described in Appendix A, Evaluation Guideline, of the DOE's
3009, Preparation Guide for
Facility Documented Safety Analyses, but instead is being used 1) as a design acceptance
criterion for confinement system performance, and 2) as an allowable public dose.
By memorandum dated May 18, 2007, (enclosed) the NNSA requested that a review of
site office and contractor mechanisms or procedures for using the 25 rem offsite dose EG
and application to approved safety bases be performed to verify that, consistent with
Appendix A, it is only being used for classification of safety controls, and not for
designing or operating defense nuclear facilities, or as an allowable dose to the public.
Further, NNSA sites were directed to clearly describe any instances where mechanisms
or procedures are found deficient, and the actions that will be taken to correct the
Our review of the NNSA site responses to the May 18, 2007, memorandum and
subsequent discussions with NNSA site office lead safety basis subject matter experts
confirms that, with the following exceptions, site office and contractor processes and
procedures only allow use of the 25 rem offsite dose EG for classification of safety
controls consistent with the guidance of Appendix A to DOE Standard 3009, and not for
designing or operating defense nuclear facilities or as an allowable dose to the public.
September 2005, contains two sections of text that need to be revised. The first is
section 4.a which states: The evaluation guidelines establish the hazardous material
doses/exposure values that the safety analysis is evaluated against. Theoretically,
individual doses/exposures exceeding the evaluation guideline should not occur at a
given point inside the evaluation area. Offsite evaluation guidelines are established
for the purpose of identifying and evaluating safety-class structures, systems, and
components. This could also be interpreted to mean that doses less than or equal to
the EG are acceptable. The second is section 30.d which states: The accident
analysis is used to quantify the hazard analysis and to bin accidents by order of
magnitude. This is done to have relative values to compare to the evaluation
guidelines that define limits allowable for both workers and the public. This
statement is wrong and must be corrected. The Office of Facility and Infrastructure
Acquisition and Operation (NA-17) is working with the
have these statements corrected in the next revision to the guide which is scheduled to
be issued by December 2007.
Based on our review, we do not believe that either of the above situations has resulted in
misapplication of the EG in the development or review and approval of the safety basis
for NNSA defense nuclear facilities.
In summary, our review has determined that NNSA site offices and contractors
understand proper use of the 25 rem EG and that it is being used correctly.
If you have any questions, please contact me or have your staff contact Rick Kendall,
NA-173 by phone at (301) 903-3102 or by e-mail at Rick.Kendall@nnsa.doe.gov.
Martin J. Schoenbauer
Principal Assistant Deputy Administrator