Basically the United States, along with other major countries of the world, is in the slow process of destroying chemical and biological munitions stockpiles.  Currently, there are still significant stores of ammunitions that are in the process of being destroyed both in the United States and in other significant countries, like Russia for example.
 These two nations have exchanged data on their aggregate stockpile size; the types of agents; percent of chemical agents in munitions, devices, or bulk containers; location of storage, production, and destruction facilities; and types of agent and munitions at each storage facility.

The following is a summation of current stockpiles that exist:

Chemical Weapons Stored in the United States and Russia
         from The Chemical and Biological Weapons Nonproliferation Project site
 

Iraq's Chemical Weapons Program
         from The Chemical and Biological Weapons Nonproliferation Project site
 

Munitions processed
        For United States munitions and stockpile disposal information,
        also for remaining tonnage of stockpile at two disposal facilities
 

Chemical and Biological Weapons Nonproliferation Project
        For general information on current conditions