**\[DNFSB LETTERHEAD\]**

November 7, 2003

The Honorable Jessie Hill Roberson

Assistant Secretary for Environmental Management

U.S. Department of Energy

1000 Independence Avenue, SW

Washington, DC 20585-O 113

Dear Ms. Roberson:

The staff of the Defense Nuclear Facilities Safety Board (Board)
recently reviewed the Transuranic (TRU) Waste Retrieval Project at the
Hanford Site. This effort includes the retrieval of more than 38,000
containers of TRU waste from the Hanford burial grounds in preparation
for processing, if necessary, and shipment to the Waste Isolation Pilot
Plant. Several hazards are presented by the TRU waste, including high
radiation levels that will require some containers to be handled
remotely and the potential for the release of radioactive material from
the containers. The Board's staff focused on these two hazards, in
particular. The results of the staffs review are documented in the
enclosed report.

The Board notes its continued concern with the 12 drums that contain
significant quantities of plutonium-238. The Board identified the need
for a disposition path for these drums in a letter dated June 11, 2002;
however, specific information regarding the retrieval, handling and
disposition of these drums still is not available.

Therefore, pursuant to 42 U.S.C. § 2286b(d), the Board requests that the
Department of Energy provide a written response within 90 days of
receipt of this letter that describes specific actions planned to:

(1) Safely retrieve and handle these 12 drums;

(2) Verify the integrity of the drums soon after retrieval and take
    corrective actions if needed;

(3) Establish a safe storage condition for these drums pending final
    disposition; and

(4) Appropriately repackage and disposition the drums.

These actions could also be applicable to other unique drums encountered
during the TRU retrieval operation.

Sincerely,

***John T. Conway***

***Chairman***

c: Mr. Keith A. Klein

Mr. Mark B. Whitaker, Jr.

Enclosure

**DEFENSE NUCLEAR FACILITIES SAFETY BOARD**

**Staff Issue Report**

October 13, 2003

**MEMORANDUM FOR:** J. K. Fortenberry, Technical Director

**COPIES:** Board Members

**FROM:** D. Qgg

**SUBJECT:** Transuranic Waste Retrieval, Hanford Site

The staff of the Defense Nuclear Facilities Safety Board (Board)
reviewed the plans of the Department of Energy (DOE) and its contractor
to retrieve buried transuranic (TRU) waste at the Hanford Site. Staff
members D. Ogg and D. Winters visited the Hanford Site during August
27-28, 2003, joined by D. Grover, Hanford Site Representative. The staff
also participated in teleconferences with site personnel on September 10
and September 17, 2003.

**Background.** The Hanford Solid Waste Operations Complex includes
eight burial grounds covering approximately 1,400 acres, and contains
low-level waste, mixed low-level waste, remote-handled TRU waste, and
contact-handled TRU waste. Between 1970 and the late 1980s, DOE placed
TRU waste drums into retrievable storage in five of these eight burial
grounds. From 1998 to 2001, DOE and its contractor removed more than
1,400 drums of TRU waste (only those drums not covered with soil) from
trenches in some of the burial grounds. However, more than 38,000 drums
and boxes of TRU waste remain covered with soil in retrievable storage.

DOE and its contractor now plan to retrieve contact-handled TRU waste
that is covered with soil. This new project, called the TRU Waste
Retrieval Project, includes the removal of drums and boxes from seven
trenches in two burial grounds (281-W-4B and 28 l-W-4C) that contain
about 90 percent by mass of the remaining TRU waste. Remote-handled TRU
may be moved during this activity but will not be processed until a new
remote-handling facility becomes available.

**Plutonium-238 Drums.** Trench 1 in burial ground 4C contains 12 unique
drums that were retrievably stored in 1977. These 12 drums contain
packaged plutonium oxide with a high plutonium-238 (Pu-238) content. The
plutonium loading in these drums ranges from approximately 200 to 500
grams per drum, about 18 percent being Pu-238.

These drums pose greater hazards than the typical drum to be handled as
part of the TRU retrieval program. The high specific activity of the
alpha-particle-emitting Pu-238 causes the packaged material and drums to
be thermally hot: a thermal analysis performed prior to placement of the
drums in the trench estimated that the centerline temperatures in the
storage containers would reach 682°F. Also, the isotopic composition of
the material would pose an internal radiation exposure hazard
considerably in excess of weapons grade plutonium in the event of an
intake.

The control for this hazard relies on the integrity of the layers of
packaging. The plutonium oxide was packaged in a robust system which
includes two sealed aluminum containers inside a metal-gasketed
stainless steel container, all inside a 55-gallon drum. However, the
lengthy storage period under higher than normal heat and radiation
fields raises concerns about the condition of the containers. DOE has
reported experience at the Savannah River Site showing aluminum
containers under similar conditions often spall and lose their
integrity. The potential for deterioration of these packages does not
support extended delay in dispositioning this high hazard material.

The Board raised concerns with these 12 drums in a letter to DOE dated
June 11, 2002. The Board pointed out that there was a need for a final
disposition path, a hazards analysis to support development of safe
retrieval and handling procedures, and an available and appropriate
facility to handle and repackage these drums. Earlier this year, the
Board's staff again raised these concerns, and the DOE Richland
Operation Office (DOE-RL) issued a Technical Assistance Request asking
for support from experts in the DOE complex in defining an appropriate
path forward. However, DOE-RL informed the staff during this site visit
that the request was denied.

The contractor currently intends to proceed with the TRU waste retrieval
activities without a firm plan for Pu-238 drums. It appears that the
tentative plan is to set the Pu-238 drums aside after they have been
retrieved and to store them above ground until a disposition path is
developed. However, many of the hot cells and shielded gloveboxes at
Hanford have been deactivated or are planned for deactivation soon, and
a new facility for remote-handled waste will likely not be available
until after 2015. This could result in keeping the drums in interim
storage for an additional decade or more after retrieval.

The Board's staff believes it would be prudent for DOE to carefully plan
for the safe retrieval and handling of these drums in the near future,
to verify the integrity of the drums soon after they are retrieved, to
establish a safe storage condition for the drums while awaiting
disposition, and to carefully consider options for the repackaging and
disposition of the drums.

**Accident Analyses.** The staff reviewed the Master Documented Safety
Analysis (MDSA) for the Solid Waste Operations Complex, which includes
the Low-Level Burial Grounds. One design basis accident of particular
interest is the single-drum deflagration accident. Contractor analysts
determined that the unmitigated consequence for a collocated worker in
this postulated accident is a dose of 260 rem (off-site consequences are
well below evaluation guidelines). Since this evaluated dose is
considered significant, the DOE Standard *Preparation Guide for U.S.
Department of Energy Nonreactor Nuclear Facility Documented Safety
Analyses*, DOE-STD-3009-94, Change Notice 2, suggests that
safety-significant controls be developed and implemented to mitigate the
hazard. Guidance from the DOE-RI, manager to the contractor on the
functional classification of safety controls requires this level of
control.

For this accident, contractor analysts proposed a safety-significant
administrative control for venting waste containers, a
safety-significant Drum Venting System, and several other administrative
control programs.

After the contractor submitted the MDSA to DOE, DOE issued its Safety
Evaluation Report and noted that additional controls were necessary for
the single-drum deflagration accident. DOE added a time limit for
staging unvented containers, as follows:

> During TRU Retrieval operations, un-vented TRU, suspect TRU, and other
> waste containers requiring venting SHALL be accumulated in batches.
> Once more than 50 containers are accumulated in a batch, a 90-day
> clock SHALL be initiated. All drums within the batch SHALL be vented
> in accordance with TSR-AC 5.6.1 within the 90-day time period. The
> total number of un-vented containers not on a 90-day clock SHALL not
> exceed 50. Backlogged un-vented containers previously identified in
> the LLBG \[Low Level Burial Grounds\] SHALL be vented within 120 days
> of the drum venting system being declared operational. A QUARTERLY
> SURVEILLANCE SHALL be performed to assure containers requiring venting
> are segregated AND accumulated batches of 50 or more containers are
> within the 90-day clock.

The contractor then added this requirement to the Container Management
program in the Administrative Control section of the Technical Safety
Requirements (TSRs), and DOE-RL approved the MDSA and TSRs.

The staff did not agree that the control set for the single-drum
deflagration accident was adequate for several reasons:

-   The mitigated frequency of the drum deflagration accident drops to
    the unlikely range, but the consequences to the worker remain high
    (i.e., 260 rem). Thus the accident presents a risk that warranted
    further control, but no additional controls were offered.

-   The administrative control dictated by DOE applies to batches of
    more than 50 drums. If work is delayed or stopped with fewer than 50
    drums accumulated, there are no time limits for venting the drums.

-   DOE-RL did not provide justification for why 90 days is an
    acceptable period of time to allow a drum to remain unvented after
    it has been handled and moved.

-   The control dictated by DOE has all the features of a Limiting
    Condition for Operation (LCO). More formality would be gained by
    designating it as an LCO in the TSRs (after addressing the issues
    noted above).

The staff's comments were transmitted to site personnel and discussed
during two teleconferences in September. As a result of these
discussions, DOE-RI, decided to make some changes in the controls,
including the following:

Unvented drums that may generate oxygen or that are bulged shall be
overpacked and then vented within 5 days.

-   Unvented drums that contain more than 6.6 curies (Pu-equivalent)
    shall be overpacked.

-   Drums containing more than 2 grams (Pu-equivalent) shall be
    accumulated in batches.

-   No more than 24 drums shall be accumulated in a batch. A batch shall
    be considered complete upon receipt of the twenty-fourth drum. Only
    one partial batch shall be accumulating during retrieval activities
    at a given time. The number of unvented containers (i.e., sum of
    complete and partial batches) requiring venting shall not exceed
    192.

-   All drums within the batch shall be vented within 30 days of the
    date on which the batch receives the twenty-fourth drum.

-   A monthly surveillance shall be performed to ensure that drums
    requiring venting are segregated, and each accumulated batch is
    within the 30-day clock.

The Board's staff views this set of TSRs as an improvement over the
previous set, and believes that the new TSRs provide some additional
conservatism. However, the staff remains concerned that no limit exists
to prevent having as many as 23 drums exposed and unvented for an
indefinite period of time. In addition, the details of how the controls
will be procedurally implemented were not available for review. The
staff plans additional discussions with the site to cover these topics.