Seeing Through Steel: INEEL Developed Technology Identifies Chemical Weapons

October 14, 1998

IDAHO FALLS, Idaho -- After a war, people try to forget. Soldiers go home, commanders retire, records get lost. Sometimes, unused ammunitions are left behind -- rusting, buried and forgotten. When such warheads are uncovered years later, the Army calls in scientists from the Idaho National Engineering and Environmental Laboratory (INEEL).

In 1988, people in the Solomon Islands discovered rusty, World War II-era U.S. artillery projectiles. The markings on the steel casings were eroded and illegible. No one knew what was in them, but something inside sloshed. A team of explosives experts realized they were dealing with chemical weapons.

The U.S. Army boxed up the munitions in airtight containers and shipped them to nearby Johnston Atoll. The 600-acre coral island, 800 miles southwest of Hawaii, has served the U.S. military since World War II as an airbase and a place to store chemical weapons.

INEEL nuclear physicist Gus Caffrey has developed a system for evaluating what's inside a projectile -- without opening it up. Caffrey and three INEEL colleagues, Don Verrill, Alan Snyder, and Brian Harlow, flew out to Johnston Atoll late this summer to assess the recovered weapons.

On Johnston Atoll, the military operates an incinerator specifically designed to destroy chemical weapons. Before a weapon can be fed into the furnace, however, the operators must know what it contains. If a warhead contained explosives rather than chemical weapons, it could destroy the incinerator. Furthermore, the incinerator operators must know what kind of chemical weapon agent is being disposed of (such as mustard gas, a nerve gas, or an arsenic compound), in order to install the correct monitors on the incinerator's filter system to check for breakdown products.

Caffrey and his colleagues tested the warheads discovered on the Solomon Islands in two ways. First, they X-rayed them with a portable, fast, digitized prototype system that they developed recently. Chemical weapon projectiles contain a distinctive blasting tube down their centers, which can be seen in an X-ray.

Second, the team used a system they developed called PINS (for Portable Isotopic Neutron Spectroscopy) to find out which kind of chemical agent filled the projectile cavities. The PINS system shoots a beam of neutrons into the projectile. The neutrons bounce into the elements that make up the chemical weapon agent, and the interaction produces gamma rays. The gamma rays are recorded as they pass back through the projectile's steel casing.

Each type of warhead fill is made up of a different set of elements. Explosives contain a lot of nitrogen; nerve gases are composed partly of phosphorous, and mustard gas is chlorine-based. When assessed with PINS, each type of weapon emits a signature pattern of gamma rays. A computer program compares the pattern to a library of chemical weapons and determines what the projectiles are filled with.

The team concluded that 75% of the Solomon Island projectiles contained mustard gas. The rest were empty or contained mustard gas breakdown products.

PINS technology is needed surprisingly often. "The Army digs up old rusty munitions all the time," said Caffrey. Such weapons may have been lost or buried, their markings may have rusted away, or their records lost. PINS can tell what is in the weapons -- and therefore how to dispose of them safely.

The team's next goal is to make a PINS prototype that is smaller and cheaper than the current model. The technology could be used by law enforcement or fire departments to detect hazardous materials, for example in drug labs or traffic accidents.

Note to editors: Project leader Gus Caffrey can be reached at (208) 526-4024, or via e-mail at ajc@inel.gov. Available photos include: four rusty warheads found on the Solomon Islands, the knee-high PINS system at work evaluating an enclosed warhead, and photos and maps of Johnston Atoll. Contact Laura Helmuth (above) for photos.
-end-


DOE/Idaho National Laboratory

Related Gamma Rays Articles from Brightsurf:

Properties of catalysts studied with gamma ray resonance
Steam-assisted oil extraction methods for heavy deposits have long been the focus of attention at Kazan Federal University.

Strange gamma-ray heartbeat puzzles scientists
Scientists have detected a mysterious gamma-ray heartbeat coming from a cosmic gas cloud.

Physicists find ways to control gamma radiation
Researchers from Kazan Federal University, Texas A&M University and Institute of Applied Physics (Russian Academy of Sciences) found ways to direct high frequency gamma radiation by means of acoustics.

Excess neutrinos and missing gamma rays?
A new model points to the coronoe of supermassive black holes at the cores of active galaxies to help explain the excess neutrinos observed by the IceCube Neutrino Observatory.

APS tip sheet: correlating matter's distribution in the universe with gamma rays
Scientists present the first direct cross-correlation between dark matter and gamma ray emissions.

APS tip sheet: High energy gamma rays
Nine Galactic sources are the highest-energy gamma -ray sources ever detected, which could suggest the presence of Galactic accelerators.

First detection of gamma-ray burst afterglow in very-high-energy gamma light
An international team of researchers observe a gamma-ray burst, an extremely energetic flash following a cosmological cataclysm, emitting very-high-energy gamma-rays long after the initial explosion.

Gamma-ray bursts with record energy
The strongest explosions in the universe produce even more energetic radiation than previously known: Using specialised telescopes, two international teams have registered the highest energy gamma rays ever measured from so-called gamma-ray bursts, reaching about 100 billion times as much energy as visible light.

Hubble studies gamma-ray burst with highest energy ever seen
NASA's Hubble Space Telescope has given astronomers a peek at the location of the most energetic outburst ever seen in the universe -- a blast of gamma-rays a trillion times more powerful than visible light.

The highest energy gamma rays discovered by the Tibet ASgamma experiment
The Tibet ASgamma experiment, a China-Japan joint research project, has discovered the highest energy cosmic gamma rays ever observed from an astrophysical source - in this case, the 'Crab Nebula.' The experiment detected gamma rays ranging from > 100 Teraelectron volts (TeV) to an estimated 450 TeV.

Read More: Gamma Rays News and Gamma Rays Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.