The U.S. Cold War-Era Chemical Weapons Stockpile

Last Reviewed
January 2024

Contact: Leanne Quinn, Chemical Weapons Convention Coalition Program Assistant, (202) 463-8270 x106

In 1990, on the heels of the Cold War, the United States possessed the world's second largest chemical weapons arsenal after Russia, consisting of more than 31,500 U.S. tons (28,577 MT) of lethal chemical agents and munitions.

Following years of bilateral talks with Russia and multilateral negotiations in the Conference on Disarmament in Geneva on chemical weapons disarmament, the United States decided in 1986 to take unilateral action to begin the destruction of its chemical weapons stockpile. The demilitarization effort was prompted by Congressional legislation (Public Law 99-145) calling for the safe destruction of the United States’ stockpile of nonbinary lethal chemical agents and related facilities.

Since transport of chemical weapons was highly contentious - and was later outright banned by Congress in 1994 (50 U.S. Code 1512a) -  the U.S. Army's chemical weapons destruction plan relied on destruction facilities located at the nine U.S. chemical weapons depots in Anniston, Alabama; Pine Bluff, Arkansas; Pueblo, Colorado; Newport, Indiana; Richmond, Kentucky; Edgewood, Maryland; Umatilla, Oregon; Tooele, Utah; and Johnston Atoll. Dustruction efforts began at the first destruction facility, Johnston Atoll, in 1990.  

By 1997, when the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction (also known as the Chemical Weapons Convention or the CWC) entered into force, the United States had destroyed only 1,434 MTs of its chemical agents and munitions. As a member state of the CWC, the United States committed to the destruction of its remaining chemical weapons inventory.

The chart below summarizes the types and quanties of chemical weapons that were once in the U.S. chemical weapons stockpile, including the agents and munitions that have already been destroyed. To date, all chemical agents and munitions stored at Aberdeen, Anniston, Johnston Atoll, Newport, Pine Bluff, and Tooele have been eliminated; the Pueblo (Colorado) and Blue Grass (Kentucky) destruction facilities are still operational.

The data are drawn from the records published by the Program Manager for Chemical Demilitarization and the U.S. Army Chemical Materials Agency in 1996, 2000, 2011, and 2012.

As of April 15 2022, there are 646.7 U.S. tons of chemical agents and munitions left to be destroyed. Official updates on the effort to complete the destruction process at the Pueblo and Blue Grass destruction facilities are available online here.

Under the provisions of the CWC, the United States must finish destroying its remaining chemical weapons by Sept. 30, 2023.

Agent Type Key:

GA – nerve agent, also known as Tabun
GB – nerve agent, also known as Sarin
HD – blister agent, sulfur mustard (nearly pure)
H – blister agent, sulfur mustard (20%-30% impurities
HT – blister agent, sulfur mustard (60% HD and 40% agent T)
Lewisite – blister agent, the central atom is arsenic
VX – nerve agent

Quantity and Type of Former U.S. Chemical Agents and Munitions by Stockpile Location

Storage SiteAgent TypeMunitionsQuantity
(number of munitions)
Start Date
End Date
Aberdeen Proving Ground, MarylandHDton containers1,818Apr 23, 2003Feb 2006
Anniston Army Depot, AlabamaHT4.2-inch cartridges183,552Aug 9, 2003Sep 22, 2011
HD4.2-inch cartridges75,360
HD105mm cartridges23,064
HD155mm projectiles17,643
HDton containers108
GB105mm cartridges74,014
GB105mm projectiles26
GB155mm projectiles9,600
GB8-inch projectiles16,026
GBM55 rockets44,738
GBM56 rocket warheads260
VX155mm projectiles139,581
VXM55 rockets35,662
Blue Grass Army Depot, KentuckyHD155mm projectiles15,492Jun 7, 2019Sept 30, 2023
GB8-inch projectiles3,977
GBM55 rockets51,740
VX155mm projectiles12,816
VXM55 rockets17,739
Johnston AtollHD155mm projectiles5,779Jun 30, 1990Nov 29, 2000
HD105mm projectiles46
HDM60 projectiles45,108
HD4.2-inch mortars43,600
HDton containers68
GBM55 rockets58,353
GB155mm projectiles107,197
GB105mm projectiles49,360
GB8-inch projectiles13,020
GBMC-1 bombs3,047
GBMK 94 bombs2,570
GBton containers66
VXM55 rockets13,889
VX155mm projectiles42,682
VX8-inch projectiles14,519
VXland mines13,302
VXton containers66
Newport Chemical Depot, IndianaVXton containers1,690May 5, 2005Aug 8, 2008
Pine Bluff Arsenal, ArkansasHTton containers3,591Mar 28, 2005Nov 12, 2010
HDton containers107
GBM55 rockets90,231
GBM56 rocket warheads178
VXM55 rockets19,582
VXM56 rocket warheads26
Pueblo Army Depot, ColoradoHT4.2-inch cartridges20,384Sep 7, 2016Sept 30, 2023
HD4.2-inch cartridges76,722
HD105mm cartridges383,418
HD155mm projectiles299,554
Tooele Army Depot, UtahH155mm projectiles54,663Aug 22, 1996Jan 21, 2012
HT4.2-inch cartridges62,590
HD4.2-inch mortar976
HDton container6,398
GB105mm projectiles798,703
GBton containers5,709
GBMC-1 bombs4,463
GBM55 rockets28,945
GBM56 rocket warheads1,056
GB155 mm projectiles89,142
GBWeteye bomb888
VXM55 rockets3,966
VXM56 rocket warheads3,560
VXton containers640
VX155mm projectiles53,216
VX8-inch projectiles1
VXspray tanks862
GAton containers4
Lewisiteton containers10
Umatilla Depot Activity, OregonHton containers2,635Sep 7, 2004Oct 25, 2011
GB155mm projectiles47,406
GB8-inch projectiles14,246
GBM55 rockets91,442
GB500-lb bombs27
GB750-lb bombs2,418
VX155mm projectiles32,313
VX8-inch projectiles3,752
VXM55 rockets14,519
VXspray tanks156

The data on this chart was sourced from the archived websites of the Program Manager for Chemical Demilitarization (June 24, 1997, Oct. 1, 2000) and the U.S. Army Chemical Materials Agency (Sept. 22, 2011; Feb. 6, 2012).