For over 70 years, a 7,000-acre spread in the foothills near Tracy, California, has been home to Lawrence Livermore’s Experimental Test Site, known as Site 300. More than 250 staff and upwards of 200 buildings and facilities at Site 300 comprise a state-of-the-art high-explosives and hydrodynamic research and diagnostics test site, furthering stockpile stewardship and weapon modernization programs. Named in succession after the other Lawrence Radiation Laboratories—Site 100 (now Lawrence Berkeley National Laboratory) and Site 200 (the Laboratory’s main campus)— Site 300 supports the national security mission with materials manufacture and fabrication; non-nuclear materials and explosive component testing; and a host of support activities from storage, inventory control, waste treatment, regulatory oversight, and environmental stewardship.
Today’s national nuclear strategy demands fast action in prototyping and production, and Site 300 serves as a centerpiece of stockpile modernization agility. Yet long-time employees recall the early 2010s when Site 300’s apparent value—and funding— dwindled. Some facilities were shuttered to ensure operation of the site’s Contained Firing Facility for critical high-explosive material testing. Equipment across the site, as well as testing processes, became outdated. In the last decade, two significant weapon programs initiated a new era at Site 300. Key process pivots and a dynamic response to the demands of weapon modernization programs not only reinvigorated Site 300 but placed it at the hub of chemists, physicists, engineers, and a complement of expert support staff working in partnership to produce, certify, and qualify weapon-scale components at a quickening pace.
A Renaissance
In 2014, the Nuclear Weapons Council initiated the W80-4 Life Extension Program (LEP) to integrate on the Long Range Standoff nuclear cruise missile in development by the U.S. Air Force. Lawrence Livermore and Sandia national laboratories work cooperatively to drive the project through study, development, and planned production. To comply with treaties in place, the W80-4 requires integration and certification without nuclear testing— motivating Site 300’s increasing development and utilization. Following the 2018 Nuclear Posture Review, the National Nuclear Security Administration named Livermore the lead nuclear design agency to replace the W78 nuclear warhead, a project that had been paused earlier. This effort, named the W87-1 Modification Program (MOD), also requires Site 300’s unique capabilities.
Livermore engineer Rachel Khavandi, who has designed and carried out hydrodynamic tests at Site 300, recalls the contrast before and after the new weapon programs. “In the early part of the 2010s, one or two hydrotests every year was considered typical,” she says. “As the LEP ramped up, a significant uptick in testing was required to support the program. The MOD efforts followed, and the volume of engineering testing grew by an order of magnitude.”
Brian Cracchiola, now deputy director of Laboratory Infrastructure, took over programmatic leadership of the Site 300 explosive facilities in 2019 as the Laboratory grew to meet the demands of the LEP and MOD. Cracchiola had led the High Explosives Applications Facility (HEAF), where small-scale experiments at the benchtop level confirm explosive material formulations for scaled-up testing. He understood the symbiotic relationship of the two facilities in the explosive material testing cycle and the new demands placed on the facilities by the weapon programs. “When Livermore received the LEP and MOD, Laboratory leadership introduced the concept of an explosives enterprise—formally bridging the gap between energetic efforts on Site 200 and larger-scale experimental support conducted at Site 300—the time had come to reinvest in our capabilities and into the science and technology space,” he says. “We needed to be more efficient, to shift away from niche tests and bespoke experiments, to generate more data, to increase our throughput. We had to change the way we worked. From 2020 forward, discussions and plans for upgrades three, five, and seven years out dominated. Today, we’re in the throes of that renaissance.”
Changing the work meant examining proficiencies, personnel, and culture. Training of explosive handlers evolved notably during this time. “We shifted away from training for small teams serving long tenures and shifted toward the concept of growing teams that operate flexibly,” says Strategic Deterrence Explosives Operations Manager Deanna Kahmke. “Now, every explosive handler receives the same basic training and grows from there. Rather than relying on information from one or two rockstar subject matter experts, we adopted a more process-driven approach and documentation. Our handlers can move between Site 200 and Site 300, as well as between facilities, and still have access to the answers they need.”
Khavandi adds that, as testing demands increased, tests became more carefully tailored from the start, in cooperation with the sponsors and stakeholders. Engineers also put more emphasis into increasing throughput to manage available resources. “We brought in a doctrinal approach. We flexed schedules, partnered more, and developed strategies for new timescales,” she says. “A higher-level planning has become the standard, and I’ve seen a shift in philosophies and capabilities to support the programs.”
An Explosives Enterprise
Even as Site 300 has steadily gained significant new capabilities and facilities since the start of Lawrence Livermore’s role in the LEP and MOD weapons programs, the Laboratory continues to put in place new opportunities to enhance and grow partnerships, advance technology, and expand expertise. The Energetic Materials Development Enclave Campus (EMDEC), including the Facility for Advanced Manufacturing of Energetics (FAME), launched in 2022 and 2023, respectively, embody the enclave model by strengthening the Laboratory’s partnerships with other national laboratories and production agencies, such as Pantex, through joint explosives synthesis, formulation, and manufacturing. (See S&TR, April/May 2024, Energizing Enclaves.)
The Pilot Plant at Site 300, opened in October 2024, adds the capability of synthesizing explosive materials at scale, and couples to the existing EMDEC formulation facility to manufacture explosive powders into plastic-bonded explosives, eliminating the need for outside partners to produce materials for weapon-scale testing. Much of the process is automated, improving accuracy and efficiency compared to facilities requiring manual adjustment. Soon-to-be-realized plans for an energetic materials production complex and new office building further secure Site 300’s key role in the national security enterprise.
The newest additions to Site 300 have made tangible the once-imagined “explosives enterprise.” Charlie Verdon led Lawrence Livermore’s weapons program (now the Strategic Deterrence Principal Directorate) from 2013 to 2018, when the Laboratory assumed a lead role in LEP and MOD. Energetic Materials Center Director Lara Leininger recalls that Verdon longed for the Laboratory to do its own prototyping, from developing new explosive material formulations to testing. “The Pilot Plant lives up to Verdon’s goal by enabling independent, full-scale experiments. Lawrence Livermore can now take an explosive material formulation from design and synthesis to manufacturing and testing and scale up without leaving the complex,” says Leininger. “In fact, in just the last few years of Site 300’s 70-plus-year history, the combination of expanded capabilities and partnerships facilitated by expert staff at every stage of operations—from inventory and oversight to explosives testing and environmental stewardship—has truly reenergized Site 300.”
The Site 300 Cycle
After explosive material formulations are confirmed in experiments at Site 200’s High Explosives Applications Facility, the designed material is manufactured in Site 300’s Chemistry Area and then pressed and machined to the desired charge shape in the Process Area. Materials undergo x-ray radiography for possible defects and, once they are cleared, are assembled for specific experiments.
Material assemblies may be subjected to mechanical testing (colloquially referred to as “shake, rattle, and roll”) in the Engineering Test Area. Such testing evaluates the assembly’s survivability from events, such as an airplane crash, extreme environmental conditions, or time.
The next destination is a firing facility, either the Outdoor Firing Facility (OFF) or the Contained Firing Facility (CFF), the world’s largest indoor firing facility. Both the OFF and CFF are used for hydrodynamic experiments. The decision whether to use the OFF or CFF depends on factors such as the type of test, the material involved, and any potential hazards associated with the test.
Experiments have traditionally been called hydrodynamic tests as the shock wave generated when test material is detonated causes the material to act as a liquid for tens of microseconds, during which time images and data are collected. The data is evaluated relative to fluid dynamics principles to understand the material’s behavior. Results are also compared to simulations based on past experiments to understand how the explosive would act in concert with special nuclear material. (See S&TR, November/December 2021, Hydrodynamic Experiments Support Stockpile Stewardship.) Components are tested without special nuclear material, yet the information gained about the specific explosive material tested enables the Laboratory to propose safer and more effective designs for nuclear weapon components.
Diagnostic tools, intricately designed to record the data needed to evaluate the experiment, are installed for each experiment. The CFF’s 18-megaelectron-volt flash x-ray, offering the world’s largest penetrating radiographic field of view, illuminates the assembly tested while sensors image the experiment from start-to-finish. Data collected at the experiment supports computer modeling to simulate other results, eliminating the time and expense of multiple firing conditions or material parameters.
Post-detonation byproducts in the CFF are removed and filtered through an automated process. Shot debris and metal are removed by Site 300 staff. The firing chamber is reencapsulated, using a painted-on coating, and then evaluated by an onsite industrial hygienist and health physicist before the CFF space can be downgraded from respiratory controls. Contaminated debris is packaged and undergoes a multifaceted, highly regulated disposal pathway. Any noncontaminated material that remains after experiments can be safely treated at Site 300’s Explosives Waste Treatment Facility.
Throughout the experimental life cycle, expert staff inspect, document, and store explosives to be tested; machinists build out experiments; health and safety professionals, including an onsite fire department, oversee operations; and maintenance staff manage water and wastewater systems. Environmental staff ensure that the more than 35 protected plant and animal species are unaffected by any Site 300 activities. (See S&TR, December 2024, Eyes on the Environment.) “Our goal is to leave the site in an even better state for the next generation of scientists and technicians,” says Lara Leininger, Energetic Materials Center director.
—Suzanne Storar
For further information contact Lara Leininger (925) 423-6573 (leininger3 [at] llnl.gov (leininger3[at]llnl[dot]gov)).
