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STATEMENT
OF
C. BRUCE TARTER, DIRECTOR
LAWRENCE LIVERMORE NATIONAL LABORATORY
UNIVERSITY OF CALIFORNIA
BEFORE
THE HOUSE ARMED SERVICES COMMITTEE
PROCUREMENT SUBCOMMITTEE
JUNE
12, 2002
INTRODUCTION
Mr.
Chairman and members of the committee, thank you
for the opportunity to provide a statement on
the status and future of the Stockpile
Stewardship Program. Dr. Michael Anastasio is
appearing before the committee today in my
absence. He is currently Deputy Director for
Strategic Operations and was recently appointed
to succeed me as Director of Lawrence Livermore
National Laboratory, effective July 1, 2002.
Livermore
is committed to maintaining confidence in the
U.S. nuclear weapons stockpile as a principal
participant in the nation's Stockpile
Stewardship Program. The Laboratory is also
engaged in vital national programs to reduce the
threat posed by the proliferation of weapons of
mass destruction and to provide for homeland
security. My message to you about the status and
future of the nation's Stockpile Stewardship
Program is consistent with my previous
testimonies before this committee:
.
A strongly supported, sustained Stockpile
Stewardship Program has an excellent chance of
ensuring that the U.S. can maintain the safety,
security, and reliability of the stockpile in
the absence of nuclear testing. It is an
extremely demanding program from both technical
and managerial perspectives with ambitious goals
and risks yet to be faced.
.
So far stockpile stewardship has achieved
many successes: certification of the W87 ICBM
warhead, which was refurbished through a
Stockpile Life Extension Program that has been
an exemplary laboratory-plant partnership;
ongoing development of a quantitative
methodology to provide the basis for weapon
certification and program decisions; the
development and use of increasingly
sophisticated stockpile surveillance
capabilities; greatly improved understanding of
many aspects of nuclear weapon performance as a
result of an aggressive program of simulations
and nonnuclear experiments; and substantial
progress in acquiring the capabilities needed
for the program to succeed in the long run.
.
However, the toughest challenges lie
ahead as weapons continue to age and other
issues and requirements for the stockpile arise.
There are currently many competing demands on
the Stockpile Stewardship Program that must be
balanced in order to succeed. At the same time,
the program needs to become more flexible and
agile so that it will be able to deal with
surprises, which are sure to come.
My
testimony amplifies on these points. First, I
discuss the need for a sustained, balanced
Stockpile Stewardship Program and efforts under
way to enhance NNSA's capabilities to develop
and execute a balanced program. Second, I
highlight selective accomplishments of the
program to illustrate that considerable progress
is being made on many fronts. Finally, I discuss
the challenges that lie ahead.
A SUSTAINED,
BALANCED PROGRAM EFFORT
These
investments in the capabilities for stockpile
stewardship are very demanding of resources. So
is the need to meet the near-term requirements
of the Department of Defense (DoD) through
stockpile life extension programs. In addition,
as pointed out in the 2002 Nuclear Posture
Review, new weapons capabilities, not present in
the current stockpile, may be needed to meet
future post-Cold War threats. Accordingly,
exploratory work on advanced weapons concepts
should be part of the overall program. Finally,
on top of all these specific demands on the
program, we need some flexibility in the
Stockpile Stewardship Program to respond to
surprises. The history of the weapons programs
is that every so often something unanticipated
arises that puts an extra demand on resources.
General
John Gordon, Administrator of NNSA, is taking a
number of actions to enhance NNSA's
performance and improve processes for long-term
planning and budgeting, which are critically
important to the development and execution of a
balanced Stockpile Stewardship Program. One key
change is the annual development of the
integrated Future-Year Nuclear Security Plan (FYNSP).
With this five-year plan, NNSA is better able to
make program trade-offs, which involve
adjustments to future-year budgets, and it helps
our Laboratory in resource, workload, and
facility planning by providing a more reliable
future program base. In addition, we expect that
the organizational changes in NNSA,
clarification of lines of authority and
responsibility, and steps to reduce
inefficiencies and excessive administrative
workload will improve the effectiveness of
programmatic efforts.
As
the two nuclear design laboratories, Lawrence
Livermore and Los Alamos are working with our
contractor, the University of California, to
strengthen management accountability, institute
more uniform best practices in operations at the
two laboratories, and better integrate our
efforts in the Stockpile Stewardship Program.
While it is essential to preserve the
independent assessment capability of a
two-laboratory system, there are many aspects of
stockpile stewardship where we share
capabilities and load-level the work. It is our
joint responsibility to ensure that there are no
significant gaps in nuclear design capabilities
and expertise, that important program milestones
are met, and that inefficiencies in effort are
minimized.
PROGRAM
ACCOMPLISHMENTS
To
date, the Stockpile Stewardship Program has many
accomplishments-we are largely on track. It
has been a team effort that has benefited from
capabilities, expertise, and hard work across
the NNSA complex-headquarters and the field,
the three laboratories, the production
facilities, and the Nevada Test Site. My
testimony describes several example
accomplishments where the Laboratory's efforts
were directly involved.
The W87 Life
Extension Program
In
April 2001, Lawrence Livermore and Sandia
national laboratories completed formal
certification of the W87 ICBM warhead, which is
undergoing a life-extension program (LEP) so
that it may remain part of the enduring
stockpile beyond the year 2025 and meet
anticipated future requirements for the system.
The W87 in the Mk21 reentry vehicle is planned
as a single RV option for the Minuteman III
ICBM. The first production unit was completed at
the Pantex Plant in February 1999, and
production is proceeding on schedule for
completion early in 2004.
This
first completed certification of a warhead
refurbished through an LEP is a groundbreaking
milestone for the Stockpile Stewardship Program.
The program was an outstanding team effort with
the Air Force, and it demonstrated effective
partnership of the laboratories and the
production facilities to overcome physics,
engineering, and manufacturing challenges to
meet Department of Defense requirements without
conducting a nuclear test. The development
activities for this program included extensive
flight testing, ground testing, and physics and
engineering analysis. High-fidelity flight
tests, incorporating the latest technological
advances in onboard diagnostic instrumentation
and telemetry, provided added confidence in the
reliability of the design modifications.
Assessment of nuclear performance is based on
computer simulation, past nuclear tests, and new
above-ground experiments that addressed specific
physics questions raised by the engineering
alterations and computer simulations.
The
W87 certification process was detailed and
thorough. It included extensive formal peer and
expert reviews by laboratory, NNSA, and DoD
personnel. Confidence in the results was greatly
strengthened by the use of a rigorous
quantitative methodology as a basis for the
certification. This methodology is discussed
below.
Certification
and Assessments
To
maintain the nuclear stockpile and to be
responsive to evolving policy, we must be able
to ensure with confidence the safety and
performance of aged and/or refurbished warheads
against their military requirements. One vital
process to build this confidence is Annual
Certification. It is based on advice from the
laboratory directors, the commander-in-chief of
the U.S. Strategic Command, and the Nuclear
Weapons Council to the Secretaries of Energy and
Defense developed from the technical evaluations
made by the NNSA laboratories. The sixth Annual
Certification cycle was completed in 2001. We
are well into the seventh and find ways to
improve the process each cycle.
In
the course of Annual Certification, our
Laboratory collects and reviews all available
information about each stockpile weapon system
for which LLNL has design responsibility,
including physics, engineering, and chemistry
and materials science data. This work is
subjected to rigorous, in-depth review by
scientists, engineers, and managers throughout
the program-including the use of "red
teams." In addition, the Laboratory's work
is reviewed by USSTRATCOM's Stockpile
Assessment Team, which provides a very valuable
critique, and several other DoD groups.
For
the assessments underpinning Annual
Certification and the formal certification
required for modified units of previously
certified and tested weapons, the key question
has transformed from "will it work?" to
"when does it fail?". When nuclear testing
is not available, these certifications will be
based on a much more extensive range of
above-ground testing, together with a vastly
improved simulation capability. The existing
nuclear test database is a crucial resource for
challenging the validity of these improved
codes. Ultimately, expert judgment informed by
the best available data will always be at the
core of the certification process.
Quantification
of Margins and Uncertainties (QMU). For
these certification actions, it is essential
that we use a rigorous set of quantitative
standards, which is technically sound-to
establish our own confidence-and which
provides transparency to the government and
military-to build their trust and confidence
in us. The methodology used in this process is
called the quantification of margins and
uncertainties (QMU).
These
standards are based on ensuring that adequate
margins exist against limited uncertainties for
each sensible way that the warhead can fail to
function properly (analogous to the engineering
safety factors used in building a bridge).
Margins must be adequate whether the concerns
are driven by aging, remanufacturing, possible
design or manufacturing flaws, or new
requirements for the warhead.
For
each issue, we gather data and conduct
simulations to determine how close we are to the
margin of failure and estimate uncertainties.
This process entails the efforts of many
experts, extensive peer group review, and
careful scrutiny by "red teams". The outcome
is quantitative confidence factors that can be
used as a basis for judgments. Livermore first
applied the QMU methodology to the certification
of the W87 life extension program. It is being
further developed and jointly implemented by
Livermore and Los Alamos as a single national
certification process.
QMU
can also help provide prioritization for the
laboratory's technical efforts and for the
overall Stockpile Stewardship Program, for
example where to invest in capabilities to raise
confidence in weapon performance. That is, QMU
can help provide direction for efforts to
improve weapon surveillance and for the Science
and Engineering Campaigns.
The
Laboratory Director's Responsibility.
As mentioned, the use of QMU helps to focus
attention on aspects of weapon design and
engineering that matter most to overall
performance. The methodology and considerable
amount of data gathered that is required for its
implementation are amenable to thorough
review-expert opinion and a multiplicity of
viewpoints are an absolutely necessary part of
the process. However, in the end, certification
is a judgement issue that ultimately rests on my
shoulders. It is my responsibility as laboratory
director.
Enhanced
Surveillance
Our
stockpile surveillance efforts focus on
assessing the condition of weapons in the
stockpile and on understanding the effect of
aging on them. Aging is important because it
affects the physical characteristics of
materials, and we must determine how these
changes impact weapon safety and performance.
With a better understanding of aging, we can
help to avoid surprise. More predictive
stockpile surveillance makes possible systematic
refurbishment and preventative maintenance
activities to correct developing problems when
necessary. The workload at the production
facilities can be better managed if burdensome
refurbishment of components that are not in
danger of failing can be avoided. An important
factor here is to be able to detect subtle
changes to the weapon system well in advance of
the change causing a safety, reliability, or
performance issue. This is essential to prepare
for and balance the workload for upgrades or
life extension efforts that may take many years
to fully implement.
We
continually review and upgrade our surveillance
programs as we gather more data, gain
experience, and refine sampling plans. We also
measure additional attributes as new tools
become available and the need for more
information arises. We are now taking on
responsibility for surveillance of pits from
Livermore-designed weapons in the stockpile to
better balance the workload. These activities
had been conducted at Los Alamos.
In
addition, we are making major improvements to
the sensors and techniques used to inspect
weapons. Newly emerging diagnostics-including
some that do not require destruction of the
weapon-are enabling us to better quantify the
condition of the stockpile and to identify aging
characteristics at the earliest possible time.
Better surveillance capabilities can help avoid
unnecessary refurbishment work at the plants.
For example, Livermore, in cooperation with
Y-12, has completed the development of an
analytical model and the development and
deployment of a suite of diagnostic tools that
enable us to understand the aging behavior of
secondary assemblies. We are also completing
development of high-resolution x-ray tomography
for imaging weapon pits; first phase deployment
at the Laboratory is complete, and deployment at
Pantex is continuing. Furthermore, development
continues on high-energy neutron radiography for
nondestructively detecting small voids and
structural defects in weapon systems.
Understanding
Plutonium
One
of the major success stories of the Stockpile
Stewardship Program is the significant
improvement we are making in understanding the
properties of plutonium. This is a very
important issue-we need to understand aging in
plutonium and the effect of aging-related
changes on the performance of an imploding pit
of a stockpiled weapon. The required capacity of
the production complex depends on the
anticipated lifetime of plutonium pits in the
stockpile. An accurate assessment is necessary.
If we underestimate the lifetime of pits, we may
overinvest in facilities to remanufacture
plutonium parts. If we overestimate the lifetime
of pits, the nation could find itself critically
short of capacity for plutonium operations when
it is vitally needed.
To
study the highly complex properties of
plutonium, we have combined advances in
theoretical modeling with the use of
sophisticated experiments. For example, we are
using advanced materials characterization tools
such as our Transmission Electron Microscope,
the most powerful such instrument in the NNSA
complex, to study how aging plutonium
accommodates the helium that is created through
self-irradiation. We are also using old pits and
accelerated-aging alloys to determine the
lifetime of pits. Accelerated-aging samples are
plutonium alloys with a mixture of isotopes to
increase the rate of self-irradiation damage so
that the material "ages" faster.
Furthermore,
Livermore is conducting sub-critical
experiments at the Nevada Test Site (NTS) to
investigate the properties of plutonium shocked
and accelerated by high explosives. NTS is also
site of the Joint Actinide Shock Physics
Experimental Research (JASPER) Facility, a
two-stage gas gun for performing shock tests on
special nuclear materials. Now that construction
is completed, JASPER will complement other
experimental and modeling activities by
providing scientists more precise
equation-of-state data at extreme conditions
than can be obtained from other types of
experiments.
Assessments
of weapon performance and certification of
weapon refurbishments must be based on
scientific and engineering demonstration to be
credible. In the absence of nuclear testing, we
rely on data from past nuclear tests as a
benchmark, component-level experiments and
demonstration, and advanced simulations for an
assessment of weapon performance and safety that
is integrated through use of the QMU
methodology. This approach has enabled us to
successfully certify the W87 life-extension
refurbishment and address stockpile issues that
have emerged to date. However, as the stockpile
ages, we anticipate that more difficult issues
will arise.
These
needs-to be able to assess and certify both
weapon performance and refurbishment
actions-drive the Stockpile Stewardship
Program's investments in much more capable
experimental facilities, such as the National
Ignition Facility (NIF), the Dual Axis
Radiographic Hydrodynamic Test Facility and even
more advanced hydro-test capabilities, and
greatly enhanced numerical simulation tools
developed through the Advanced Simulation and
Computing (ASCI) program. Here, the discussion
focuses on three areas where significant
improvements in capabilities are completed or
under way at Livermore: the Contained Firing
Facility, ASCI, and NIF.
The
Contained Firing Facility. Hydrodynamics
testing is the most valuable experimental tool
we have for diagnosing device performance issues
for primaries in stockpiled weapons. Through
hydrodynamics experiments conducted at
Livermore's Site 300 and the Dual-Axis
Radiographic Hydrodynamic Test Facility (DARHT)
at Los Alamos, weapon scientists are able to
characterize the energy delivered from the high
explosives to a mock pit, the response of the
pit to hydrodynamic shocks, and the resulting
distribution of pit materials when they are
highly compressed. This information is critical
for baselining weapons, certifying stockpile
performance, and validating hydrodynamics
simulation codes.
Over
the past decade, we have made tremendous
advances in diagnostics capabilities and
experimental techniques used in hydrodynamic
testing. We are now able to gather far more
revealing data from hydrodynamic tests than was
possible when we developed the weapons that are
now in the stockpile. The most sophisticated
type of hydro experiment is the "core
punch," in which scientists use high-energy
radiography to record a digital image of the
detailed shape of the gas cavity inside a pit
when it is highly compressed. In 1998, we
carried out at Livermore's Flash X-Ray
Facility the first core punches on two important
stockpile primary devices: the W76 SLBM warhead
and the B83 strategic bomb.
An
upgrade of the Flash X-Ray Facility was
completed last year with the addition of the
Contained Firing Facility. The project was
completed on time, on budget. Qualification
testing has been completed to assure its ability
to contain debris from experiments that use up
to 60 kilograms of high explosives. The first
stockpile-related experiment was executed in
March 2002. Livermore is now able to conduct
these critically important experiments with
isolation from the surrounding environment.
ASCI
and the ASCI White Computer. The
Advanced Simulation and Computing (ASCI) program
is central to many of the success stories of the
Stockpile Stewardship Program. ASCI has steadily
progressed from efforts to develop weapons
physics and engineering codes that run
efficiently on the new computers to a resource
that the LEPs are counting on to meet important
milestones. As we continue to get larger and
faster machines and better simulation models,
the ASCI capabilities we have are "deployed"
in support of a wide range of Stockpile
Stewardship Program deliverables.
In
summer 2000, we took delivery from IBM of ASCI
White, at the time the world's most powerful
computer, capable of 12.3 teraops (trillion
operations per second). This machine has been
successfully used and shared since early 2001 by
all three NNSA laboratories-Sandia and Los
Alamos were extremely effective in using it by
computing at a distance. To meet each
laboratory's requirements to run problems,
calculations were interleaved in an integration
schedule for the machine.
Both
Livermore and Los Alamos used ASCI White to
complete in late 2001 the first-ever prototype
fully three-dimensional simulations of a
complete warhead explosion. The
size and scale of ASCI White allowed the two
laboratories to employ a level of spatial
resolution and depth of physics models that were
heretofore completely beyond reach in 3D. Sandia
also used ASCI White to perform structural
dynamics calculations for different environments
that weapons might encounter.
One terabyte of core memory was used on each
structural dynamics calculation in simulations
that were completed in late September 2001 and
set many world records. The speed, large
memory, and stability of White were essential
elements contributing to these successful series
of calculations.
ASCI
White is more than fully subscribed, and new
capabilities are soon to be delivered to Los
Alamos and Sandia. Livermore is earmarked to
take delivery of its next ASCI computer in FY
2004, a machine that will be capable of 60 to
100 teraops. It will move us much closer to
ASCI's goal of full-scale simulation of
weapons performance using advanced physics
models with data derived from extensive,
first-principles physics simulations. The
groundbreaking ceremony for construction of the
Terascale Simulation Facility (TSF) to house
this computer was held April 4, 2002.
The
National Ignition Facility (NIF).
The High Energy Density Physics (HEDP) effort is
a critical element of the Stockpile Stewardship
Program. It is the source of experimental data
to support ongoing LEPs and data to support the
longer-term effort to provide predictive
capability and quantitative measures for warhead
certification into the future. The National
Ignition Facility (NIF) is the central
experimental facility in the HEDP Program.
Housing a 192-beam laser and associated
experimental capabilities, NIF will be the
world's largest laser, delivering 60 times
more energy density than the Omega laser at the
University of Rochester (and the previous Nova
laser at Livermore), currently the largest laser
in the HEDP program.
NIF
is the only stewardship facility that will
provide experimental conditions relevant to
fusion burn, a critical process in the operation
of a nuclear weapon. NIF will be capable of
addressing underlying physics issues associated
with our stockpile weapons, and the ability to
conduct integrated experiments at
weapons-relevant temperatures and pressures.
These integrated NIF experiments will allow us
to experimentally validate our computational
capabilities, under conditions more closely
matched to those encountered in actual
underground tests. In addition, NIF will be an
important tool for evaluating the judgement of
the stewards, based on the ability to predict,
or not, the outcome of complex weapons-relevant
experiments.
Construction
is continuing on
NIF. Overall the NIF project is more than 60%
complete. In September 2001 the NIF conventional
facilities construction, a $270 million project,
was completed on schedule and on budget. In May
2002, the Project completed installation of
one-half of NIF's beampath infrastructure. Now
in place are the precision-cleaned enclosures
for the components of 96 laser beams. In
addition, we continue to make outstanding
technical progress on NIF's optical systems.
Great progress has been made on the development
of new optics polishing techniques that can
reduce the damage potential of NIF optics much
more than our requirements. We are currently
implementing these new techniques at our vendors
to provide the first optics for NIF's final
focusing systems.
The
baseline plan and schedule for NIF was included
in General Gordon's certification of the NIF
project, provided to Congress on April 6, 2001.
The schedule provides for project completion at
the end of FY 2008, and the NIF team's goal in
the coming year is to achieve "first light"
by delivering four laser beams to the target
chamber. Experimental plans have been developed
to utilize the NIF as it is brought on line.
These early experiments have been designed to
provide data to support LEP activities and to
begin to provide some of the data required to
improve our ability to determine margins against
credible failure modes. As commissioning of
laser beams continues, NIF will quickly become
the workhorse experimental facility in the HEDP
program.
PROGRAM
CHALLENGES
First,
to recognize and evaluate aging issues (and
other defects) in weapons and devise remedies
before they become problems, we must understand
in detail the science and technology that govern
all aspects of nuclear weapons. We are making
progress here, but we need even better
investigative tools. Enhanced surveillance
capabilities and a better understanding of aging
effects in weapon components will help to avoid
surprise and provide a longer lead to time for
refurbishment actions.
The
nuclear weapons production complex must be
flexible and able to remanufacture parts and
refurbish weapons as needed. There will be
requirements for new weapon components.
Investments in production facilities are
required to support urgently needed
refurbishment actions in current LEPs and to
begin to deal with widespread obsolescence in
the production complex. The plants need
efficient and modern means for manufacturing
weapon components. In addition, we need to
proceed expeditiously with studies of plutonium
aging and the W88 Pit Manufacturing and
Certification Integrated Project. These efforts
will provide an informed basis for future
decisions about a plutonium pit production
capability.
We
also must be responsive to new requirements and
prepared to deal with surprises. DoD requires
that NNSA retain the capability to design,
develop, and produce new-design nuclear
warheads. By engaging in studies and exploratory
research and development for advanced weapon
concepts, we can exercise weapon development
capabilities, help to avoid surprise and
understand threats, and become better positioned
to respond to new weapon requirements should
they emerge. In addition, these activities will
serve to train new designers and engineers, and
they will reinforce ties to DoD and its
contractors. Interactions with the plants about
manufacturing issues will also be beneficial.
Since
the future is uncertain and surprises do occur,
we need nuclear-test readiness. In conjunction
with the other laboratories and the Nevada Test
Site, Livermore is participating in NNSA's
examination of measures that can be taken to
shorten the time between a decision to conduct a
nuclear test and the event. Together, we need to
determine the longest lead-time items and costs
to shorten them in order to make reasonable
trade-off decisions to cost-consciously improve
readiness.
The
nation must be confident in the results of
Annual Certification and our assessments of the
performance of aging and refurbished warheads as
well as any new weapons that are developed.
Expert judgement is required, backed by
experimental data, the results of validated
simulation models, and application of a
rigorous, quantitative certification
methodology. We need to press ahead to further
refine and fully implement the QMU certification
methodology together with acquisition of
advanced computation and experimental
facilities: more powerful ASCI computers, modern
laboratory experimental facilities, NIF and
DARHT, and then an advanced hydrotest facility.
These capabilities are essential elements of the
Stockpile Stewardship Program's Campaigns and
efforts to improve our fundamental understanding
of nuclear weapons, which are essential for
assessments and certification.
Finally,
acquisition of this spectrum of capabilities is
time urgent to meet existing requirements for
weapon refurbishment and to deal with other
weapon performance issues as they arise. At the
same time, the LEP workload is substantial, and
the program needs to become more flexible and
agile so that it will be able to deal with
surprises, which are sure to come. There are
currently many competing demands on the
Stockpile Stewardship Program that must be
balanced in order to succeed.
Program
balance depends on having strong, sustained
support for the Stockpile Stewardship Program,
and we are benefiting from this committee's
continuing support. Program balance also depends
on having quality leadership by the NNSA
management team, effective systems and tools for
comprehensive program planning, and efficient
program execution. We are pleased with General
Gordon's actions to provide NNSA clear
direction, make necessary organizational
changes, improve long-term planning and
budgeting, and make NNSA a more effective and
efficient organization. We are already seeing
some benefits from these actions and expect to
see more in coming years.
CLOSING
REMARKS
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