A federal official says it could be at least another year before more than 15,000 aging chemical weapons stored at the Blue Grass Army Depot in Madison County can be disposed of.
A project manager says an assessment of the proposal to explode some of the weapons still must be completed.
He said the main concern is with mustard gas shells.
A sampling showed that 85 percent had some solidification of the active agent in them.
As assessment will look into the possible impact the neutralization process could have to human health and the environment.