Here is the original documentary I watched. There is more information on the individual sites on more recent news and magazine sites, often referenced on wikipedia:
There was a good NBC dateline documentary about it years ago. The biggest stockpiles were being dismantled slowly, but they were indeed leaking, and it was a gargantuan project to neutralize the weapons and containers full of VX. I'm not sure where we're at now. I'll look it up later when I'm home.