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Are They Already Cutting Corners on Worker Protection at DOE’s New Plutonium Processing Plant?

plutonium is toxic at the scale of micrograms, deadly at the scale of milligrams, and useable in nuclear weapons of mass destruction at the scale of kilograms. This is why plutonium work requires rigid, intensive safety systems, referred to as “defense in depth,” to protect workers and the surrounding people and landscape; as well as extreme levels of security and material accounting.

CounterPunch, BY DON MONIAK 11 Sept 23

As of this past Labor Day, there are strong indications that future workers at the planned, new Savannah River Plutonium Processing Plant (SRPPF) may face unnecessary, increased risks of exposure to radiological hazards inherent in plutonium toxicity and chemical complexity.

According to an August 3, 2023  letter from the Defense National Facilities Safety Board (DNFSB) to the Department of Energy’s (DOE) National Nuclear Security Agency (NNSA), the SRPPF project leadership team does not consider vital plutonium processing safety equipment as “safety significant controls.”

According to the letter, NNSA’s project leadership team believes a reliance on worker sense of sight, hearing, taste, smell, and touch is sufficient to detect and/or prevent accidents such as plutonium fires and dispersal of plutonium oxide powder.

In the hierarchy of nuclear safety,  the Department of Energy standards place “Safety Significant Controls” above administrative controls that are reliant upon the absence of human error.

The motive for SRPPF project team’s preference for administrative controls is unknown.

The New Plutonium Processing Plant. 

The plutonium/MOX (Pu/MOX) fuel facility was a massive, multi-billion dollar endeavor designed to help dispose of dozens of tons of surplus nuclear weapons plutonium (Pu). This Savannah River Site(SRS) project was abandoned in the late 2010’s, following a chronic array of technical issues, mismanagement, major cost overruns, cutting of corners, and the lack of commercial Pu/MOX fuel customers.

After the project was abandoned, the Department of Energy’s (DOE) National Nuclear Security Agency (NNSA) decided to repurpose the unfinished facility into a new “plutonium pit”production plant. The Mixed Oxide Fuel Fabrication Facility (MFFF) was then renamed the Savannah River Plutonium Processing Plant (SRPPF).  This $11 billion plus repurposed facility is already burdened by cost overruns—-the original estimate was $3.7 billion.

Plutonium pits are referred to as the primary nuclear explosives, or triggers,” (1) that dominate the known U.S. nuclear weapons arsenal. Pits acquired their quaint nickname by virtue of the resemblance of the configuration of high explosives surrounding the primary nuclear explosive to stone fruit like peaches and plums—an example of early nuclear weaponeers’ inside humor.

The Pu pits are pressure vessels with nested shells of material, comprised of other non-nuclear parts, including the metal cladding, welds, a pit tube, neutron tamper(s) and initiator, as well as the usually hollow-cored plutonium hemispheres. In most pit designs, a sealed pit tube carries deuterium-tritium gas into the hollow-core to boost the nuclear explosive power of weapons.

But unlike the sweet, fruity, and and delectable flesh surrounding plum and peach pits, a Pu pit is surrounded by a high explosives package powerful enough to implode the plutonium metal sphere contained in the pit. This is not like compressing a tin can, as plutonium is the most durable of the transuranic heavy metals.

The current plan is to annually produce at least eighty new plutonium pits in the SRPPF. Pit fabrication was once the exclusive task at the long-closed Rocky Flats plant in Colorado, and the work processes constitute the most dirty—in terms of waste production—and dangerous workplace in the national nuclear weapons complex. In this century, Los Alamos National Laboratory (LANL) has failed miserably to reconstitute a tiny fraction of the Rocky Flats pit production rate.

Pit production is unlikely to be the only task at the SRPPF.  An estimated ten to twelve-thousand surplus plutonium pits, containing a sum of 30 to 34-metric tonnes of plutonium, could also be processed at a plutonium pit disassembly and conversion line at the SRPPF. The resulting plutonium oxide powder would then be sent to the SRS K-Area’s Pu waste production facility, where the powder is diluted to a three to five percent level within a larger mixture of inert materials………………………….

Some Plutonium Processing Hazards

There is a negligible level of debate that plutonium is toxic at the scale of micrograms, deadly at the scale of milligrams, and useable in nuclear weapons of mass destruction at the scale of kilograms. This is why plutonium work requires rigid, intensive safety systems, referred to as “defense in depth,” to protect workers and the surrounding people and landscape; as well as extreme levels of security and material accounting.

The most hazardous plutonium operations involve plutonium pit fabrication. After pit disassembly, the plutonium within pits is converted to a finely dispersed powder form (2), made up of sticky grains containing energetic alpha particles that easily damage soft lung tissues. Sticky plutonium oxide particles clinging to ductwork can also hinder ventilation systems over time.

Recycling plutonium for pit production then requires difficult and dangerous processes to remove impurities and undesirable decay products such as intensely radioactive Americium-241. (3) The resulting plutonium form is transferred to the next step, the plutonium foundry.

The foundry work involves a complex ten-step process, summarized as melting, casting, and heat treating of plutonium metal. Gallium is added at a one-percent ratio to produce an alloy that is considered almost as easy to machine as aluminum or silver. The risk from explosion, criticality, and spill hazards must be rigidly controlled; while contaminated parts such as crucibles pose unique waste management measures.

The final plutonium processing step is machining the foundry product into a precise sub-critical configuration. Like any machining, Plutonium metal work casts tiny shavings and creates fine dust.

These shavings can ignite upon exposure to air and lead to larger fires that can destroy glove boxes and ventilation systems, and cause large releases of plutonium into the atmosphere. The Rocky Flats experience suggests that fires of any size are not a remote possibility, they are a probability.

The task is to keep Pu metal fires small and nondestructive, while preventing injury and harmful exposures to workers. A small fire can render costly equipment useless. A large fire can lead to a countryside contaminated with particles that become more intensely radioactive for decades.

Extreme care must also be taken to keep plutonium metal in a non-critical configuration at all times. The wrong geometry or placement of metal pieces in the wrong configuration can produce the deadly blue light that signifies criticality accidents. In 2009, a number of Los Alamos criticality engineers walked off the job at the lab’s pit production line, citing a casual approach to criticality safety.

The final step is assembly, where the parts that make pits tick are introduced. The making of these parts pose their own toxic hazards, such as the fine dust from machining beryllium metal.

Those are just several aspects of the safety issues involved with the plutonium pit fabrication.

The True, and False, Necessity for New Pit Fabrication and Production. ……………………………………………………………………………………………………………………………………………………………………………….

The Pit Plant’s Initial Design: One Less Layer of Safety Depth?

Because of all these factors, new pit production is considered essential, and a new, smaller scale—by Cold War Standards—plutonium pit fabrication capacity is presently in the preliminary design phase at the SRPPF complex.

The highest standards of safety are expected to prevent accidents or mitigate the impacts of spills, fires, leaks, and dispersion of fine radioactive dust. A less rigid approach to safety is quite unexpected for a high hazard, hardened nuclear facility that would only be the second its kind in the weapons complex—-the last being the Rocky Flats plant built in the 1950’s.

But according to the August 3, 2023  letter from the Defense Nuclear Facilities Safety Board (DNFSB), the DOE/NNSA’s project leadership team does not consider vital plutonium processing safety equipment as “safety significant controls.”…………………………………………………………………………………………………………………………………………………………………………………………….more https://www.counterpunch.org/2023/09/11/are-they-already-cutting-corners-on-worker-protection-at-does-new-plutonium-processing-plant/

September 12, 2023 Posted by Christina Macpherson | - plutonium, employment, safety, USA | Leave a comment