Hearing on the Global Nuclear Energy Partnership

**Testimony of**

**Neil E. Todreas**

**before the**

**Senate Energy and Natural Resources Committee**

**November 14, 2007**

Good morning, Chairman Bingaman and Ranking Member Domenici. My name is
Neil Todreas and I am a Professor of Nuclear Science and Engineering
(emeritus) at the Massachusetts Institute of Technology.

It is an honor to be called before you to discuss the subject of the
Global Nuclear Energy Partnership, a matter of considerable importance
to the future of nuclear energy. I have been asked to address the state
of the technology needed for the execution of GNEP.

As an overall characterization let me be clear that DOE is only at the
start of a very significant program of technical research & development,
a program being conducted by a large team of dedicated and expert
professionals which will require multiple decades of scientific and
engineering accomplishment. Nevertheless I believe such an R&D program
to evaluate the potential of nuclear energy systems operating in the
closed fuel cycle is an important national undertaking. I do so for
reasons of ensuring national influence in the global evolution of fuel
cycle technology as well as creating closed cycle technologies
(separations, fuel fabrication, transmutation and reprocessing)
sufficient to demonstrate that nuclear technology can recycle its spent
fuel if called upon to do so.

Regarding the first reason as I've noted previously[^1], "There are
basically three costs of the U.S. not supporting separation technology
going forward. First, and most importantly, we will lack the technical
knowledge to be credible and influential in the evolution of commercial
nuclear power. Second, we will not acquire the knowledge necessary to
develop effective safeguards for operating reprocessing facilities in
other nations. Third, we will not acquire the knowledge to permit us to
make timely and informed judgments about long-term options for closed
nuclear fuel cycles that may be of importance in future generations."
These costs dictate that we pursue such R&D. The second reason is that
enlarging the options for spent fuel management is a prudent step in the
expected scenario of increasing nuclear power deployment.

Regarding GNEP technologies let me start with the three facilities
needed to demonstrate the key technologies

1.  A Consolidated Fuel Treatment Center (CFTC), which will conduct LWR
    spent nuclear fuel separations( and later commercial reprocessing of
    burner reactor transmutation fuel.)

2.  A prototype Advanced Burner Reactor (ABR) that will demonstrate
    transmutation of actinides and fast reactor technology

3.  An Advanced Fuel Cycle Facility (AFCF) to develop the reprocessing
    and fabrication technologies needed for test transmutation fuels and
    eventual recycling of ABR cores using Transmutation Fuel. It will
    provide the experience needed to design, license, and operate a
    commercial scale facility for recycling the ABR core's Transmutation
    Fuel.

A major decision for the CFTC and ABR is the appropriate scale for these
facilities. The recent NAS review[^2] makes a strong case for the
initial construction of smaller engineering versus large-scale
facilities for both the LWR spent fuel separation facility and the
burner reactor (a 100 -- 200 MT/yr separation facility and a 50 to 100
MWe advanced burner test reactor are suggested). Additional reasons I
would add to this case are the need for caution in the scaleup from
bench-scale separations success and the need for a flexible and
dedicated irradiation test bed for transition fuel development and
qualification.

Underlying the determination of readiness to proceed with even such
engineering scale demonstrations is the assessment of the readiness of
the technologies to be used. Hence I now turn to the technologies being
developed and evaluated for operations and design of these facilities.

-   Separations of LWR spent fuel in the CFTC -- Several approaches are
    being considered. UREX+ which has been under development for some
    years in our national laboratories, principally ANL and two
    commercially controlled processes COEX and NUEX. Each of these
    processes meet the GNEP Statement of Principles that pure plutonium
    will not be separated, although importantly the Principles do not
    reference the required chemical or isotopic diluents which must be
    combined with the separated plutonium. The COEX and NUEX processes
    would produce a mixed Uranium (U) and Plutonium (Pu) oxide product
    (exact proportions likely differ between processes) suitable for
    thermal reactor recycling. The UREX+ suite includes a series of
    processes which extract various actinides and fission products in
    groups or individually (processes +1 through +4). These UREX
    processes can yield transuranics (TRU[^3]) material for fabrication
    into transmutation fuel for irradiation in fast reactors or inert
    matrix fuel for transmutation in a thermal reactor. Transmutation of
    TRU material in fast reactors as well as thermal reactors is
    discussed later under the ABR heading.

> The key GNEP requirements for these separation processes are being
> developed as Criteria, e.g. total process losses of radiotoxic
> actinides from separations and fabrication activities of 0.2% ;
> specific separations efficiencies for U, minor actinides[^4] and key
> fission products ; and a scalable process meeting international
> safeguards norms (facility metric tonnage per year capacity has not
> been yet set --total national capacity needed could be about 2000
> MT/yr of LWR spent fuel whereas existing international facilities are
> about 800MT/yr ) as well as General Goals, e.g. limited emissions and
> high-level liquid waste production fuel cycle costs causing no more
> than a 10% increase in LWR busbar cost of electricity; repository
> acceptable waste forms ; and a licensable facility.\
> \
> Key among these requirements are the efficiency of separation and the
> associated degree of acceptable losses of actinides and fission
> products to waste streams, losses which must be controlled to avoid
> burdening rather than assisting spent fuel waste management. A major
> output of the solicitation of commercial interest now underway is to
> learn what industry believes is feasible regarding such specific
> requirements .\
> \
> The DOE selected reference technology is UREX +1a ( its separated
> products are U, Technetium ,Cesium/Strontium, TRU and all other
> fission products). As of summer 2007 it had only been demonstrated at
> bench-scale over short times with fresh solvents. Hence variations in
> process chemistry over the long term have not been established.

-   Fabrication and Demonstration of Transmutation Fuel for the ABR --
    the ABR will most likely be started with traditional sodium fast
    reactor driver fuel, not fuel with transuranic isotopes (TRU). As
    the core loadings undergo recycling, and since multi-recyclings are
    required to effectively transmute the plutonium and minor
    actinides,[^5] fuel elements with TRU content are required. These
    are called transmutation fuels and require a significant fabrication
    and long irradiation testing program. A significant fabrication
    program is needed because large-scale remote fabrication consistent
    with hot-cell operations must be developed. Further, for oxide fuels
    the effect of Americium (Am) due to its high vapor pressure on the
    fabrication process is unknown as is the effect of lanthanide
    fission products on the fuel's required oxygen-to-metal atomic ratio
    and irradiated materials properties, both of which impact achievable
    fuel pin performance. For the alternative metal fuel, large-scale
    fabrication without loss of Am due to its volatility must be
    developed and again the effect of lanthanides but here on potential
    fuel cladding chemical interactions must be resolved.[^6]\
    \
    A long period of development is needed because the fuel elements
    must be irradiation tested in a fast neutron reactor of which none
    exists in the US and only a few are available worldwide. First
    technical feasibility is to be established by fuel pellet
    fabrication and irradiation of short pellet stacks in a simulated
    fast neutron environment in the thermal Advanced Test Reactor (ATR)
    in cadmium shrouded test positions. This work has been underway for
    several years. Next , engineering feasibility will be established by
    irradiating long length pins in the fast reactor environment.
    Activities to initiate this phase are also ongoing. Finally fuel
    qualification will be achieved by producing a fuel pin and fuel
    assembly product that are suitable for licensing.

> For the transition of the ABR core load to Transmutation Fuel , lead
> test assemblies (LTAs) are contemplated for insertion in the ABR As
> successful irradiation experience is gained the ABR core will be
> gradually loaded with recycled transmutation fuel. However, this
> concept of demonstrating satisfactory LTA operation in a commercial
> reactor as well as the gradual transition in that reactor core to a
> full transmutation fuel loading runs counter to the prevailing fuel
> performance approach in our commercial fleet. Specifically, the US LWR
> commercial industry is adopting a goal of zero fuel failures by 2010.
> It is likely that commercial acceptance for operations of a core load
> of Transmutation Fuel will require prior demonstration of failure-free
> operation of multiple core loads of identical fuel in a non-commercial
> facility. These factors dictate that qualification of transmutation
> fuel for ABR performance will be a long and costly process- longer
> than the 10 year period currently envisioned. The GNEP program
> properly has Computation and Simulation as a major research
> ingredient. It is my hope and expectation that the transmutation fuel
> development and demonstration will be increasingly impacted by such
> simulation capability, a capability which could decrease the time and
> cost of in-reactor irradiations by development of sufficiently
> accurate models of fuel behavior under irradiation and their exercise
> by faster-than-real-time computation.

-   The Design and Construction of the ABR -- The GNEP ABR is envisioned
    as a sodium-cooled fast reactor, commercially designed, constructed
    and operated. The choice of sodium coolant is plausible based on a
    balancing of its inherent characteristics and the extensive,
    although not uneventful, worldwide operating experience of the late
    20^th^ century. Further, the benefits of coordination with existing
    sodium reactor programs of all major nuclear development countries
    favor the choice of sodium over alternative concepts whose
    development is far less advanced. Nevertheless, an evaluation of
    competing reactor technologies using a systematic set of selection
    criteria as pointed out in the NAS report would be most desirable.\
    \
    For any type fast reactor selected for GNEP, and especially for the
    sodium option, two principal challenges for technology development
    are the generation of a design of sufficient

    1.  safety characteristics as well as the development of a
        risk-based, technology neutral framework for pursuing its
        licensing and

    2.  a capital and operating cost profile such that it can gain
        commercial acceptance

> The DOE has properly engaged industry to address these sodium reactor
> design strategies. Important systems engineering studies underway are
> also addressing what the performance requirements of these reactors
> should be, chief among them the value of the core conversion ratio
> which impacts the number of fast reactors and processing facilities
> needed. System studies should also evaluate the proposal below for a
> thermal recycle program component which was raised in my 2006
> testimony and in a minority view of the NAS study.
>
> It is obvious that deployment of fast reactors in numbers sufficient
> to make a meaningful transmutation contribution is far in the future.
> Our operating LWR fleet is a ready resource in which to conduct
> thermal neutron transmutation on a schedule dictated by development
> and qualification of suitable fuel materials. In the inert matrix fuel
> option, a portion of the core is loaded with inert matrix fuel
> composed of TRU and inert material, thereby eliminating the U238
> isotope which would if present transmute to Pu239, a material we set
> out to transmute and thus eliminate in the first instance. Inert fuel
> development, although already extensively studied internationally, has
> challenges, key among them the reprocessing of diluent material, which
> will require considerable further work although likely less than that
> needed for fast reactor transmutation fuel. This two-tiered fuel cycle
> option of first thermal reactor transmutation followed by reprocessing
> and then fast reactor transmutation of the resulting vastly limited
> quantity of TRU should be evaluated for the GNEP program. This
> strategy has the potential to accelerate the start of transmutation of
> TRU material and also reduce the number of fast reactors needed for
> the ultimate disposition of TRU from the LWR fleet's spent nuclear
> fuel.

-   Grid Appropriate Reactors -- GNEP proposes small-scale reactors for
    developing economies for which fresh fuel would be provided and
    spent fuel returned to the supplier states. GNEP also designates
    these as "proliferation-resistant international modular reactors"
    (PRIMR). As I noted in 2006, "The small scale is not necessitated by
    the fuel cycle but rather the electrical grid and capital structure
    of the developing economy. Such a supply and spent fuel return
    arrangement would provide adequate proliferation safeguards in an
    era of worldwide expansion of nuclear technology. It is, however, by
    no means certain that the capital and fuel cycle costs of these
    small-scale reactors would yield an attractive cost of electricity
    (COE) for these economies. Considerable R&D needs to be supported by
    DOE to refine such designs to a level where realistic COE can be
    projected and proliferation-resistant effectiveness assessed,
    especially if fast spectrum design options are to be considered.
    There are, however, some innovative LWR designs already existing and
    pebble bed reactors being developed in South Africa and China that
    offer considerable advances in reactor safety features which bode
    well for introduction of nuclear power into technically
    unsophisticated nuclear economies, if competitive COE can be
    achieved." The laboratory proposal is for a dual-path approach for
    PRIMR development and demonstration. A fast-track deployment of a
    near-term reactor to gain US leadership in the rapidly emerging
    global nuclear market in support of GNEP objectives and a second
    path of specific technology development and demonstrations needed to
    deploy second generation PRIMR concepts. A suitable number of
    concepts exist for the first path. The development targets for the
    second path must yet be established. This will be done through an
    assessment of user country needs and constraints in concert with the
    international community leading to the development of a set of PRIMR
    system requirements.

In conclusion the development of technology needed for GNEP is a large
and technically demanding task. Significant activity is underway which
is facing and working through the resolution of multiple technical
challenges. No insurmountable barriers exist to my knowledge although my
recent exposure to these extensive development programs has been limited
by the inactivity of the Nuclear Energy Research Advisory Committee and
consequently its key oversight activity in this area, the Advanced
Nuclear Transformation Technology Subcommittee. The scale, ownership,
timing, and ultimate cost of the principal GNEP facilities are key
strategic questions. Their answer depends on many factors --among them
very importantly the continued progress and results of this development
program.

**Appendix A**

**Sources Consulted**

1.  DOE websites: [www.gnep.gov](http://www.gnep.gov/) or
    www.gnep.energy.gov

2.  Advanced Fuel Cycle Initiative, FY 2008 Congressional Budget
    Request, February 7, 2007

3.  P. Lisowski, GNEP Presentation to Nuclear Energy Research Advisory
    Committee (NERAC), February 20, 2007

4.  J. Rempe et al., Status Report to NERAC. Advanced Nuclear
    Transformation Technology Subcommittee of the Nuclear Energy
    Research Advisory Committee, February 21, 2007

5.  F. Goldner, USDOE, "GNEP Transmutation Fuel Development,"
    Presentation to the 2007 Regulatory Information Conference, March
    15, 2007

6.  Report of Advanced Nuclear Transformation Technology Subcommittee of
    the Nuclear Energy Research Advisory Committee, April 2, 2007

7.  Fast Reactor Technology. Chris Grandy, Manager, Engineering
    Development and Application Department, Nuclear Engineering
    Division; Presentation to GAO, May 24, 2007

8.  F. Carré, The Nuclear Fuel Cycle: Generation IV Nuclear Energy
    Systems' Sustainability and Transition from LWRs, American Nuclear
    Society Annual Meeting, Boston, Mass., June 26, 2007

9.  A. Hanson, Near-Term Options for Treatment and Recycle. American
    Nuclear Society Annual Meeting, Boston, Mass., June 26, 2007

10. Global Nuclear Energy Partnership Technology Development Plan,
    Global Nuclear Energy Partnership Technical Integration Office, July
    25, 2007

11. A. Griffith, Global Nuclear Energy Partnership. Advanced Fuel Cycle
    Facility (AFCF), Office of Nuclear Energy, U.S. Department of
    Energy. GNEP Annual Meeting, October 2, 2007

12. Review of DOE's Nuclear Energy Research & Development Program,
    National Research Council, Released October 29, 2007

13. P. Broussard, CEA R&D Program in France on Advanced Fuel Cycle
    Processes. International Symposium: Rethinking the Fuel Cycle. MIT,
    Center for Advanced Nuclear Energy Systems, Cambridge, Mass., Oct.
    30-31, 2007

14. P. Hejzlar, Do We Need Fast Actinide Burners for Waste Management?
    International Symposium: Rethinking the Fuel Cycle. MIT, Center for
    Advanced Nuclear Energy Systems, Cambridge, Mass., Oct. 30-31, 2007

15. J. J. Laidler, Technology Options for Spent Fuel Recycling.
    International Symposium: Rethinking the Fuel Cycle. MIT, Center for
    Advanced Nuclear Energy Systems, Cambridge, Mass., Oct. 30-31, 2007

16. D. Stout, Director, Office of Light Water Reactor Spent Fuel
    Separations Recycling Used Nuclear Fuel (CFTC Project), November 7,
    2007

[^1]: My testimony of April 6, 2006 before the Subcommittee on Energy,
    Committee on Science, United States House of Representatives

[^2]: Review of DOE's Nuclear Energy Research & Development Program,
    National Research Council, Released October 29, 2007

[^3]: Plutonium (Pu),Neptunium (Np),Americium (Am) and Curium (Cu)

[^4]: Neptunium (Np),Americium (Am) and Curium (Cu)

[^5]: Various,although not particularly attractive options exist for
    minor actinide management other than irradiation of a homogeneous
    mixture with plutonium in fast reactors eg. storage (of Curium),
    target elements, and a minor actinide- only fueled reactor due to
    the special characteristics of the principal minor actinides
    Americium, Neptunium, and Curium.

[^6]: Frank Goldner, USDOE, "GNEP Transmutation Fuel Development,"
    Presentation to the 2007 Regulatory Information Conference, March
    15, 2007 as quoted in the NAS study cited in footnote 2