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| Courtesy American Meteorological Society Images from a 2010 Ammonia Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Ammonia Dissemination test at the Dugway Proving Grounds. Al Hartmann | The Salt Lake Tribune Dugway Proving Ground was locked down Wednesday night due to a mislabeled vial of nerve age | Courtesy American Meteorological Society Images from a 2010 Ammonia Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Ammonia Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Chlorine Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Ammonia Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Ammonia Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Chlorine Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Chlorine Dissemination test at the Dugway Proving Grounds. Chris Detrick | The Salt Lake Tribune "London Fog" Program Manager David Blanchard speaks during a public comment meet | Courtesy American Meteorological Society Images from a 2010 Chlorine Dissemination test at the Dugway Proving Grounds. Chris Detrick | The Salt Lake Tribune "London Fog" Program Manager David Blanchard speaks during a public comment meet | Courtesy American Meteorological Society Images from a 2010 Chlorine Dissemination test at the Dugway Proving Grounds. | Courtesy American Meteorological Society Images from a 2010 Chlorine Dissemination test at the Dugway Proving Grounds.