Dugway Proving Grounds finishes demolition tests
Washington, July 15, 1997 (GulfLINK)--The DoD completed a series of small-scale demolition tests on May 31, 1997 at Dugway Proving Grounds in Utah. These tests were conducted to better understand what happened when U.S. troops destroyed munitions at the Khamisiyah ammunition storage facility following the Gulf War in March 1991.
The seven tests, conducted jointly by DoD and CIA, were designed to discover how the rockets in the Khamisiyah pit area exploded and how chemical agent may have been dispersed. The test results will help answer two major questions: (1) who may have been exposed to chemical agents at Khamisiyah and (2) to what extent they may have been exposed.
Significant questions still remain regarding possible exposure of troops during and soon after the demolition. Based on information made available by the United Nations Special Commission (UNSCOM) and a review of intelligence information, DoD and the CIA presumed that chemical agent released as a result of the demolition of rockets in a bunker, known as bunker 73, and in an area known as the "pit."
The CIA modeled the potential chemical fallout from bunker 73 and published their findings in August 1996. Using military testing from the 1960s, the CIA obtained a good understanding of what happens to chemical releases when rockets are detonated in a structure, like a bunker. But modeling of the pit demolition has posed a more difficult challenge.
"What were trying to do is find out how the agent reacts relative to the storage crates; find out how much could have been released; find out if there are sympathetic detonations; these types of questions," explained Robert Walpole, CIA Special Assistant for Persian Gulf War Illnesses issues during a DoD press conference on May 1, 1997.
In preparation for the tests, an array of data-collection equipment was set up in the vast, open desert area of Dugway Proving Grounds in Western Utah. Several towers reaching more than 100 feet formed a vertical grid of detection instruments to collect air samples. Scattered on the ground were white print flex cards used to measure the droplets of simulant that fell to the ground. The cards captured the pattern of ground dispersion following each test. High-speed cameras recorded the blasts.
DoD used foreign-produced 122 millimeter rocket engines and U.S. manufactured warheads. The warheads were filled with the simulant triethyl phosphate, a non-toxic substance with physical properties similar to the nerve gas sarin. "Warheads were faithful to the design of those in the pit at Khamisiyah," said Col. Larry Cereghino, director of Priority Action and Analyses at the Office of the Special Assistant for Gulf War Illnesses.
Detonations of individual and multiple rockets were included in the series of trials. The first trial provides test experts information to make refinements in the layout of instrumentation to ensure operational readiness of the experimental design and instrumentation for the remainder of the tests.
Plastic explosive compound four (C4) was placed the same way soldiers who conducted the demolitions said it had been placed on warheads at the Khamisiyah site. A series of three more single rocket tests were then conducted.
At the second trial, an individual rocket in its original crate container was placed one meter off the ground with a charge at the end of the warhead. Explosive ordnance disposal personnel attempted to detonate the rocket based on the same approach used by the soldiers at Khamisiyah. Technicians observed that the rocket did not explode, but broke open and spilled its contents on the ground.
The third and fourth single rocket trials provided substantial information on how much material dispersed, how it vaporized, and how far it traveled into the air. By dyeing the simulant red, the manner in which it saturated the wooden crates and scattered across the landscape was readily observable.
The next two trials were executed to determine the sympathetic detonation of surrounding rockets and warheads when an explosive is deliberately attached to rockets in a stack. The final and largest test involved the explosion of nine rockets simultaneously.
"Soldiers at Khamisiyah did not have enough explosives to set a charge on every rocket in a stack," explained Cereghino. "According to personal accounts from the soldiers, they had enough explosives to place a charge on one out of every nine or 10 rockets."
While it is impossible to exactly replicate events at the Khamisiyah site, the Dugway test attempted to replicate the ratio of rockets to explosives at the time of detonation in March 1991. Strain gauges and pressure sensors were placed on certain rockets to measure blast pressures and the kind of force applied to the surrounding rockets. The rocket stack tests produced effects consistent with pictures taken of the Khamisiyah storage facility a few days after the demolition of the pit area.
In order to answer the question of what would happen to rockets which may have been ignited at Khamisiyah and thrown into the air, test experts at Dugway dropped a rocket from 5,000 feet, as part of a final test, to observe the reaction upon impact. The rocket bored 30 feet into the ground without breaking open or leaking material. The experiment indicated that these rockets were more likely to penetrate the ground on impact and less likely to explode. This outcome was anticipated since the munitions at Khamisiyah were unfused rockets in storage.
While the Dugway testing provided a tremendous amount of data on the quantity, rate of release, and dispersal of the liquid simulant, Col. Cereghino noted the limitations of the experiment.
"Testing is just one piece of the puzzle in understanding what happened at Khamisiyah," he said. "We have no way of reconstructing exactly where every charge was, the exact purity of the agent involved, and the exact weather conditions at the moment the explosion occurred. While all of those things will never be known absolutely, we have greatly reduced the uncertainty about what happened."
With advice from a national panel of technical experts convened by the Institute for Defense Analyses, DoD and CIA will jointly develop the best available model to determine what happened at Khamisiyah and who might have been exposed.
The CIA, Naval Surface Warfare Center, Defense Special Weapons Agency, and the Naval Research Lab will apply the data derived from the Dugway experiments to computer models, which will then be used to predict the direction in which the chemical agent sarin traveled, how far and how fast, and at what concentration.
The U.S. Army Center for Health Promotion and Preventive Medicine will then use the plume model to study health consequences.
"Knowledge gained from the testing will enable DoD to make a more accurate estimate of individuals who may have been exposed to sarin as a result of the demolition," Cereghino concluded.
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