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8
Summary
In Chapters 3 through 6, the committee identifies a significant list of
research topics, summarized in Table 8.1, where the EMSP can make a
significant contribution in addressing HLW cleanup problems through
its long-term basic research activities. The motivation driving the selec-
tion of research activities is to provide contingency approaches and to
improve process effectiveness, as explained below:
· Providing contingency approaches. The purpose of the recom-
mended research activities is to reduce technological risk by
focusing on potential problems that could disrupt the current
EM-H LW management program. Part of the recommended
research for waste pretreatment and immobilization are aimed
toward this objective.
· Improving process effectiveness. The purpose of the recommend-
ed research activities is to improve the effectiveness of the differ-
ent HLW process areas (characterization, retrieval, pretreatment,
immobi I ization, and tank closure). Research recommendations
focus on better characterization methods for monitoring process
functions, separation techniques to remove bulk non-hazardous
material from the HLW streams, and methods to achieve higher
waste loading in the immobilized waste forms.
Table 8.1 summarizes the recommended long-term research activi-
ties and identifies those providing contingency approaches and those
improving process effectiveness. Some research activities could lead to
both contingency approaches and process improvements. For instance,
investigating the effect of crystal content in borosilicate glass is a con-
tingency approach against problems with future waste streams but also
could improve the effectiveness of the current immobilization process
by increasing the waste loading. Table 8.1 also indicates whether the
S u m m a r y
83
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TABLE 8.1 Summary of the ~ong-term basic research objectives where the EMSP can make significant contributions in
accressing HEW cleanup problems.
Time Scale
Purpose of
Research Objectives
Identified Future Improved
Long-Term Basic Research Problem Potential Contingency Process
Objectives (where the EMSP can (affecting Problem Approach Effectiveness
make significant contributions cleanup (the next (to reduce (to reduce
in addressing HLW cleanup operations few technology risks,time,
Process Area problems) now) decades) risks) end costs)
Characterization Develop remote-sensing instruments X X
(Chapter 3) Develop on-line or in situ instruments X X
Improve solids-liquid separation methods X X X
Retrieval and Improve underlying science and technology X X X
pretreatment for sludge leaching operations
(Chapter 4) Increase the efficiency of liquid X X X
decontamination methods
Immobilization Identify alternative immobilization media to X X
(Chapter 5) overcome limitations of borosilicate-glasses
Investigate the effect of increased crystal content X X X
on the durability of the borosilicate glass matrix
Improve phenomenological models to predict
long-term leachability of various glass
waste forms
Evaluate advantages of using unreacted
glass-forming chemicals versus premelted
glass frit
X X
X X X
Understand the mechanism offoaming in X X
Joule-heated melter
Mitigate effects of precipitation of noble metals X X
and crystalline phases in Joule melters
Improve Joule-heated melters to achieve X X X
higher processing temperatures
Develop alternatives to Joule-heated melting X X
Tank closure and Develop highly innovative and effective retrieval X X X
other long-term methods for removal of residual HLW from
issues the tanks
(Chapter 6) Develop highly innovative and effective retrieval X X X
methods for removal of HLW materials from
the pipelines
Improve characterization of residual waste in tanks X X X
Develop non-invasive near-field monitoring X X
techniques
Improve near-field containment methods X X
through use of barriers
aDetails can be found in the chapters indicated in parentheses.
H I G H - L E V E L vv A s I t
~ A ~
84
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recommended research addresses already identified or future potential
problems. Some of the recommendations may address both types of
problems. For instance, improving the characterization of residual waste
. . . . . . .
. . . . .
s
.
prior to rank closure Is a problem that has been already identified by
DOE. However, the first priority is to remove the bulk of the waste from
the tanks, and only two tanks (see Chapter 6) have been closed so far.
Nevertheless, this issue will become more pressing in the future, when
retrieval of the bulk of the waste will be completed and the main task
will be tank closure.
Programmatic Considerations for the
EMSP Research Portfolio
In selecting long-term research topics for its portfolio, the EMSP
should take into account technological risk and the following desired
attributes. Examples and rationales for the recommendations are pro-
vided in Chapter 7.
Managing Technological Risk
A technological risk in HEW management is the risk that existing
technologies will fail to accomplish goals and performance require-
ments set by environmental remediation policies or regulations. The
EMSP can contribute to reducing technological risk by funding a basic
research program focused on alternative processes and improved
approaches to current baseline plans, as recommended in the foregoing
chapters. It is important that the sites and EM collaborate to build
research roadmaps identifying technological risk and including contin-
gency approaches.
Desired Attributes of the EMSP-H[W Research Portfolio
In selecting projects for future proposal cycles, the committee rec-
ommends consideration of the following attributes for the EMSP
research portfolio:
maintaining long-term vision,
maintaining relevance,
providing for contingencies,
de ve lop ing working re la lion sh ips, a n d
prioritizing objectives.
S u m m a r y
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The committee recognizes that the EMSP cannot address all of the rec-
ommended research areas equally in the next few years, nor can its
portfolio acquire all of the recommended program attributes immedi-
ately. However, the EM cleanup program is a planned multi-decade
effort costing several billion dollars. Current plans to treat and dispose
of HLW are fraught with technical uncertainties, and many of the
planned treatment activities are first-of-a-kind efforts presenting enor-
mous technical chal lenges.
The recommendations in this report address contingency approach-
es or improvements to the current HLW management baseline plans.
The committee is aware of DOE's commitments and of the difficulties in
implementing changes, both from a technology and regulatory point of
view. However, given the long-term duration of this planned cleanup
effort, it is expected that new technologies will emerge and that greater
scientific understanding will be achieved in the next decades. The
EMSP is the ideal setting in which to develop truly innovative
approaches to the management of HLW in tanks and bins that could
lead to scientific breakthroughs in the future. If a scientific break-
through can help reduce risks, cleanup time, and costs, regulations can
be revised accordingly and obstacles to implementing changes at the
sites can be removed. In this respect, the EMSP is a small but vital ele-
ment1 to the long-term success of the EM cleanup mission.
This conclusion was also reached by the Ad Hoc Committee on Science and
Innovation of the Environmental Management Advisory Board in EMAB (2001 ).
H ~ G H - L E V E E W A S T E
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Representative terms from entire chapter:
contingency approaches
