"Small number of degraded chemical weapons recovered
On June 21, 2006 the U.S. House of Representatives Permanent Select Committee on Intelligence released key points from a classified report from the National Ground Intelligence Center on the recovery of chemical munitions in Iraq. The report stated that "Coalition forces have recovered approximately 500 weapons munitions which contain degraded mustard or sarin nerve agent." However, all are thought to be pre-Gulf War munitions.[113]
These munitions meet the criteria of weapons of mass destruction, according to the commander of the National Ground Intelligence Center. "These are chemical weapons as defined under the Chemical Weapons Convention, and yes ... they do constitute weapons of mass destruction," Army Col. John Chu told the House Armed Services Committee. The munitions addressed in the report were produced in the 1980s, Maples said. Badly corroded, they could not currently be used as originally intended, though agent remaining in the weapons would be very valuable to terrorists and insurgents, Maples said"
http://en.wikipedia.org/wiki/Iraq_wmds#Small_number_of_degraded_chemical_weapons_recovered