**\[DNFSB LETTERHEAD\]**

June 19, 2006

The Honorable Linton Brooks

Administrator

National Nuclear Security Administration

U.S. Department of Energy

1000 Independence Avenue, SW

Washington, DC 20585-0701

Dear Ambassador Brooks:

For the past several years, the Department of Energy (DOE) has been
developing the capability to stage, assess, and support disposition of a
damaged nuclear weapon or improvised nuclear device at the Nevada Test
Site (NTS), in case such a situation should arise. DOE identified
G-Tunnel at NTS as the facility to be used for staging and assessing a
damaged weapon or device suspected of being too unstable to be taken
directly to nuclear explosive facilities at the Pantex Plant or the
Device Assembly Facility (DAF) at NTS. Although the National Nuclear
Security Administration (NNSA) has improved the condition of G-Tunnel in
recent years, essential improvements for life safety and safe nuclear
explosive operations remain to be accomplished.

In a letter to NNSA dated March 28, 2005, the Defense Nuclear Facilities
Safety Board (Board) expressed concern about the slow progress being
made in developing and moving forward with a defined action plan for
addressing known problems with G-Tunnel. The Board requested that NNSA
identify the desired conditions of readiness for G-Tunnel, including
facility and equipment improvements, and provide its plan and schedule
for establishing those conditions. On July 25, 2005, NNSA responded with
a plan that addressed currently identified safety issues, inadequacies
in the Documented Safety Analysis, and facility maintenance needs. The
plan indicated the actions to be taken would be completed in about 4
years.

Continued evaluation by the Board's staff revealed that the upgrades
identified in NNSA's plan would take approximately 10 years to
accomplish given the resources being applied. The Board discussed this
issue with NNSA's Associate Administrator for Emergency Operations
(NA-40) on February 8, 2006, and the Board's staff held a follow-up
discussion with NA-40 staff and NNSA's Chief of Defense Nuclear Safety.
These discussions indicated that NNSA is reevaluating its plans to
upgrade G-Tunnel in light of recent decisions that potentially reduce
the scope of the mission for the facility. NNSA's current expectation is
that operations in G-Tunnel to address an improvised device will be of
extremely short duration (i.e., no more than 3 days). On this basis,
some upgrades at G-Tunnel are still likely to be pursued, but NNSA has
not yet identified their scope or schedule. For a damaged nuclear
weapon, NNSA currently expects disposition to occur at the Pantex Plant
or DAF without involving G-Tunnel.

The basis for the contemplated change in mission for G-Tunnel is not
clear. A damaged nuclear weapon may not be stable enough or sufficiently
characterized to risk taking it directly to Pantex or DAF, both of which
house activities essential to DOE's defense nuclear complex and the
continuing viability of the nuclear stockpile. Likewise, an improvised
nuclear device may need to be staged at G-Tunnel for more than a few
days. Thus, having a facility, other than Pantex or DAF, prepared to
stage and assess a problematic device safely for more than a few days
appears necessary. NNSA's current assumption of disposition within a few
days contrasts with preparations made by the nuclear weapons design
laboratories, which anticipate potentially several weeks to assess and
dispose of a weapon or device. The laboratories developed the capability
and practiced to respond to emergencies with damaged nuclear weapons and
improvised nuclear devices over the past two decades and were key to the
development of the capability to dispose of such a weapon or device at
NTS.

Accordingly, pursuant to 42 U.S.C. § 2286b(d), the Board requests that
within 60 days of receipt of this letter, NNSA provide a report
describing its plans for the staging, assessment, and disposition of a
damaged nuclear weapon or improvised nuclear device; the scope of the
mission for G-Tunnel and other facilities to be used for such
activities; and the plan and schedule for identifying applicable
requirements and desired conditions of readiness for the facilities and
accomplishing any needed facility upgrades. This report should address
how the requirements of Title 10 of the Code of Federal Regulations,
Part 830, *Nuclear Safety Management*, will be met for these facilities
and activities.

Sincerely,

***A. J. Eggenberger***

***Chairman***

c: Mr. Thomas P. D'Agostino

Admiral Joseph J. Go1

Dr. Jay H. Norman

Mr. Mark B. Whitaker, Jr.