Munitions unitary

The Department of Defense Authorization Act of 1986 (Public Law 99-145) directed the Secretary of Defense to destroy all lethal unitary chemical munitions and agents by September 30, 1994, including organophosphate nerve agents such as GB. The act was amended in 1988 (Public Law 100-456) to allow for complete disposal of chemical munitions by April 1997. 

The unitary5 chemical agents in U.S. stockpiles are nerve agents (GB and VX)6 and three related forms of blister (mustard) agent (H, HD, and HT). The original stockpile contained 31,496 tons of unitary agents, which were stored in a variety of munitions and containers under ambient conditions, where they exist primarily as liquids. Because the stockpile at Johnston Atoll in the Pacific has been completely destroyed by incineration and the stockpile at Deseret Chemical Depot, in Utah, has been partially incinerated, as of October 3, 2001, the amount in storage was approximately 24,098 tons. 

The term unitary indicates a single chemical loaded in munitions or stored as a lethal material. More recently, binary munitions have been produced in which two relatively safe chemicals are loaded into separate compartments to be mixed to form a lethal agent after the munition is fired or released. The components of binary munitions are stockpiled in separate states. They are not included in the present CSDP, but they are being destroyed in a separate program. 

Following the experiences at the Rocky Mountain Arsenal during Project Eagle, an experimental facility to test multiple destruction technologies was constructed at Tooele Army Depot in Utah as the Army began to consider destruction of obsolete unitary munitions.In 1982, after substantial internal and external review of the test results from the Tooele facility, incineration was selected for future destruction of chemical weapons. Johnston Atoll, over 800 miles south-west of the Hawaiian islands, was chosen as the site for the first full-scale incinerator facility. 

GA, a unitary chemical munition, inhibits AChE, the enzyme responsible for the breakdown of the neurotransmitter ACh. When inhaled, its toxicity is half that of sarin. It depresses plasma and RBC-AChE activities significantly in the blood. At 20-25% of red blood cell AChE baseline, the effect of the nerve agent becomes noticeable. There is no evidence of systemic toxicity other than the cholinesterase activity (Parker et al, 1990 Munro et al, 1994). GA has not been shown to produce OPIDN except at extremely high doses. The cardiac effect of GA conforms to OP-caused arrhythmias and AV block. 

Industrial production of sulfur mustard was discontinued in 1968 at that time, the US stockpile contained some 17 000 tonnes (ATSDR, 2003). The US unitary chemical weapons stockpile includes sulfur mustard which was originally present in various munitions and tonne containers at the Aberdeen Proving Ground in Maryland, Deseret Chemical Depot in Utah, Anniston Army Depot in Alabama, the Umatilla Depot Activity in Oregon, Pine Bluff Arsenal in Arkansas and Tooele Army Depot in Utah (DOD, 1996). HD, H and HT are stored in various containers and munitions at these and several other nonstockpile sites. Destruction of the remaining stockpile, either by hydrolysis or incineration, is presently underway. Incineration of nearly 4000 tonnes of... 

There are certain chemical munitions, materiel, and facilities that are not specifically included in the U.S. stockpile of unitary chemical weapons (those containing a single lethal chemical agent). These items are referred to as nonstockpile chemical warfare materiel and consist of binary chemical weapons, miscellaneous chemical warfare materiel, recovered chemical weapons, former chemical weapon production facilities, and buried chemical warfare materiel. 

OR) (Carnes 1989 Army Chemical Materials Agency at www.cma.army,mi ). "Unitary munitions are loaded with undiluie, finished CW agent, as opposed to binary munitions, in which agent precursors mix and react to form finished agent after the munition is fired. 

The U.S. Army has been directed to dispose of the stockpile of unitary chemical weapons by Public Law 99-145 and subsequent amendments. The chemical weapons stockpile consists primarily of the agents VX, HD, and GB, ich are contained in a variety of munitions and bulk containers. These chemical agents are distributed among eight sites in the continental United States (CONUS), as well as at Johnston Atoll in the Pacific Ocean awaiting a distraction method and approval. 

This procedure, however, is connected with high danger for inspectors due to (e q>eded) leakage of unitary munitions. Therefore, air monitoring within the fiamework of the verification will be at the same time a measure of workplace safety fi om the point of view of inspedor, and of course, of handling personnel. 

Another major issue the designer has to address is whether to build a binary or unitary weapon. So-called unitary munitions contain the CW agent already in its completed toxic form, while binary weapons maintain two separate chambers one component mixes with the other to produce the CW agent before reaching the target. 

Unitary munitions may take the form of a shell, rocket, bomb, or canister filled with the CW agent, and only a fuse needs to be added before firing. Flowever, unitary munitions are dangerous to store, handle, and transport. Binary munitions, which are generally considered a significant improvement in design, reduce the likelihood of serious accidents, especially if the two components are kept apart until the last possible moment. The US 155-mm artillery munition utilized a binary system that combined the precursor chemicals difluor (p-p) and isopropyl alcohol to produce sarin. 

---