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Dugway sheep incident

The Dugway sheep incident, also known as the Skull Valley sheep kill was a 1968 sheep kill that has been connected to United States Army chemical and biological warfare programs at Dugway Proving Ground in Utah. Thousands of sheep were killed on ranches near the base, and the popular explanation blamed Army testing of chemical weapons for the incident, though alternative explanations have been offered. A report first made public in 1998 was called the "first documented admission" from the Army that a nerve agent killed the sheep at Skull Valley.



Since its founding in 1941, much of the activity at Dugway Proving Ground is a closely guarded secret. Many activities included aerial nerve agent testing.[1] According to reports from New Scientist, Dugway was still producing small quantities of anthrax as late as 1998, 30 years after the United States renounced chemical and biological weapons.[2] There were at least 1,100 other chemical tests at Dugway during the time period of the Dugway sheep incident. In total, almost 500,000 pounds (230 metric tons) of nerve agent were dispersed during open-air tests.[1] There were also tests at Dugway with other weapons of mass destruction, including 328 open-air tests of biological weapons and 74 dirty bomb tests and the equivalent of eight intentional meltdowns of nuclear reactors.[1]


In the days preceding the Dugway sheep incident the United States Army at Dugway Proving Ground conducted at least three separate operations involving nerve agents.[3] All three operations occurred on March 13, 1968. One involved the test firing of a chemical artillery shell, another the burning of 160 U.S. gallons (600 L) of nerve agent in an open air pit and in the third a jet aircraft sprayed nerve agent in a target area about 27 miles west of Skull Valley. It is the third event that is usually connected to the Skull Valley sheep kill.[3]

The incident log at Dugway Proving Ground indicated that the sheep incident began with a phone call on March 17, 1968 at 12:30 a.m. The director of the University of Utah's ecological and epidemiological contract with Dugway, a Dr. Bode, phoned Keith Smart, the chief of the ecology and epidemiology branch at Dugway to report that 3,000 sheep were dead in the Skull Valley area. The initial report of the incident came to Bode from the manager of a Skull Valley livestock company.[4] The sheep were grazing in an area about 27 miles from the proving ground; total sheep deaths of 6,000–6,400 were reported over the next several days as a result of the incident.[5] The Dugway Safety Office's attempt to count the dead sheep compiled a total of 3,483.[6]

Possible causes

The most obvious explanation in the aftermath of the incident was that a chemical or biological agent had escaped from the Dugway Proving Ground. Logic dictated that for 3,000 sheep to suffer a near instant death, an agent from Dugway would almost have to be involved.[4] Circumstantial evidence seemed to support this assertion, the United States Army admitted to conducting open-air tests with the nerve agent VX in the days preceding the sheep kill.[4] The Army also intimated that a spray nozzle had malfunctioned during the test causing an aircraft to continue spraying VX as it climbed to higher altitudes.[4][5] It was also reported that a small amount of VX was found in the tissue of the dead sheep.[5]

Other information contradicted the initial assumptions about the cause of the incident. One contradiction to nerve agent exposure as a cause came in the symptoms of some of the sheep following the incident.[6] Several sheep, still alive, sat unmoving on the ground. The sheep refused to eat, but exhibited normal breathing patterns and showed signs of internal hemorrhaging.[6] Regular breathing and internal hemorrhaging are inconsistent with nerve agent exposure.[6] In addition, no other animals in the area, some much more susceptible to nerve agent poisoning, were affected.[4][6]


The incident had impact on the Army, and U.S. military policy within a year. The international infamy of the incident contributed to President Richard Nixon's decision to ban all open-air chemical weapon testing in 1969.[1] The sheep incident was one of the events which helped contribute to a rise in public sentiment against the U.S. Army Chemical Corps during and after the Vietnam War.[7] Ultimately, the Chemical Corps was disbanded for a short time as a result.[7]

Following the incident, the Army and other state and federal agencies compiled reports, some of which were later characterized as "studies".[3] A report which remained classified until 1978 and unreleased to the public until nearly 30 years after the incident was called the "first documented admission" by the Army that VX killed the sheep. In 1998, Jim Woolf, reporting for the The Salt Lake Tribune, made the content of the report public for the first time.[1] The report described the evidence that nerve agent was the cause of the sheep kill as "incontrovertible."[3] The 1970 report, compiled by researchers at the U.S. Army's Edgewood Arsenal in Maryland, stated that VX was found in both snow and grass samples recovered from the area three weeks after the sheep incident.

The report concluded that the "quantity of VX originally present was sufficient to account for the death of the sheep.[3] Even after the report surfaced the Army maintained that it did not accept responsibility for the incident nor did they admit negligence.[1] As late as 1997, one year before the report went public, U.S. Department of Defense officials stated that "it (the report) was never published is because it wasn't particularly revealing."[8]

See also


  1. ^ a b c d e f Norrell, Brenda. "Skull Valley's Nerve Gas Neighbors", (LexisNexis), Indian Country Today (Rapid City, South Dakota), October 26, 2005. Retrieved 26 November 2007.
  2. ^ Hambling, David. "US army plans to bulk-buy anthrax", New Scientist, 24 September 2005. Retrieved 27 November 2007.
  3. ^ a b c d e Woolf, Jim. "Army: Nerve Agent Near Dead Utah Sheep in '68; Feds Admit Nerve Agent Near Sheep", (LexisNexis),The Salt Lake Tribune, January 1, 1998. Retrieved 26 November 2007.
  4. ^ a b c d e Regis, Edward. The Biology of Doom: The History of America's Secret Germ Warfare Project, (Google Books), Owl Books, 2000, p. 209, (ISBN 080505765X). Retrieved 26 November 2007.
  5. ^ a b c Hoeber, Amoretta M. and Douglass, Jr. Joseph D. "The Neglected Threat of Chemical Warfare", (JSTOR), International Security, Vol. 3, No. 1. (Summer, 1978), pp. 55-82. Retrieved 26 November 2007.
  6. ^ a b c d e Mauroni, Albert J. America's Struggle with Chemical-Biological Warfare, (Google Books), Praeger, Westport, Connecticut: 2000, p. 40, (ISBN 0275967565). Retrieved 26 November 2007.
  7. ^ a b Mauroni, Al. "The US Army Chemical Corps: Past, Present, and Future", Army Historical Founation. Retrieved 26 November 2007.
  8. ^ "DoD news briefing - Mr. Kenneth Bacon, ASD (PA)," (Lexis Nexis, relevant excerpt), M2 Presswire, April 8, 1997. Retrieved 26 November 2007.

Further reading

  • Boffey, Philip M. "Nerve Gas: Dugway Accident Linked to Utah Sheep Kill", (Citation, log-in required to view article) Science 27 December 1968, Vol. 162, No. 3861, pp. 1460 - 1464. Retrieved 26 November 2007.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Dugway_sheep_incident". A list of authors is available in Wikipedia.
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